著者

Tao Tian Yajie Lu Jun Yao Xin Cao Qinjun Wei Qi Li

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.18-00006, (Released:2018-08-31)

参考文献数

27

被引用文献数

8

---

Autosomal dominant non-syndromic hearing loss (ADNSHL) is characterized by postlingual progressive onset. Due to its high genetic heterogeneity, it is difficult to perform a molecular diagnosis for most patients with ADNSHL. In our study, whole-exome sequencing (WES) was used to screen pathogenic gene candidates by analyzing genomic DNA samples from a large Chinese family (JSNY-067), including the proband and her father, who suffered from non-syndromic hearing loss. The pathogenicity of candidate nonsynonymous variants in ADNSHL genes was evaluated by co-segregation analysis in family members by direct PCR and Sanger sequencing. Furthermore, multiple in silico analyses (SIFT, Polyphen2, PROVEAN and MutationTaster) and molecular dynamics simulation were used to assess the potential pathogenicity of the candidate mutations. We identified a novel causative mutation, c.622A>G in MYO6 (DFNA22), that resulted in a p.K208E substitution. This mutation co-segregated with the hearing loss phenotype in extended family members, and was predicted to be pathogenic by SIFT, PolyPhen2, PROVEAN and MutationTaster. Furthermore, molecular dynamics simulation analysis revealed that the p.K208E substitution had a limited influence on the whole protein structure and stability, but that it could affect the locations of the sidechains of nearby hydrophilic residues, which in turn resulted in the sidechains of Asn186 and Glu190 being exposed more frequently at the surface of the protein. WES has thus been shown to be a useful molecular diagnostic tool in screening uncommon gene mutations associated with hereditary hearing loss.

著者

Makoto T Hayashi

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.92, no.3, pp.107-118, 2017-06-01 (Released:2018-01-20)

参考文献数

132

被引用文献数

15

---

The ends of eukaryotic linear chromosomes are protected from undesired enzymatic activities by a nucleoprotein complex called the telomere. Expanding evidence indicates that telomeres have central functions in human aging and tumorigenesis. While it is undoubtedly important to follow current advances in telomere biology, it is also fruitful to be well informed in seminal historical studies for a comprehensive understanding of telomere biology, and for the anticipation of future directions. With this in mind, I here summarize the early history of telomere biology and current advances in the field, mostly focusing on mammalian studies relevant to aging and cancer.

著者

Wenqing Zhu Xiaoguang Luo Atif Adnan Peifu Yu Siyi Zhang Zhixin Huo Qin Xu Hao Pang

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.17-00038, (Released:2018-03-30)

被引用文献数

6

---

Genome-wide association studies have reported numerous candidate loci associated with Parkinson's disease (PD). NUCKS1 and INPP5K are two such candidate loci, although they have rarely been reported in Asian populations. To explore these potential genes for PD susceptibility, we investigated the association between PD and two SNPs, rs823114 and rs1109303, located on the NUCKS1 and INPP5K genes, respectively, in the Han population of northern China. We genotyped the two SNPs using the multiplex PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) technique. A total of 685 subjects including 322 sporadic PD patients and 363 healthy controls were recruited from the population. After Bonferroni correction, our results suggested that there was a significant association of a minor allele (G) in rs823114 with reduced risk of PD development (P = 0.017, OR = 0.768, 95%CI = 0.618 - 0.955), and the difference in genotypes between the PD patients and healthy controls was significant under the dominant model (GA+GG vs. AA). After stratification by gender, males had a lower risk than females (P = 0.008, OR = 0.666, 95%CI = 0.495 - 0.898). However, the distribution of genotype frequency exhibited no significant differences between the PD and control groups (P > 0.025) in INPP5K rs1109303 (P = 0.048, OR = 0.806, 95%CI = 0.650 - 0.998). We conclude that NUCKS1 rs823114 indicates a decreased risk of susceptibility to PD and shows a male genetic distribution bias in the Han Chinese population.

著者

Makoto T Hayashi

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.17-00010, (Released:2017-10-06)

被引用文献数

5 15

---

The ends of eukaryotic linear chromosomes are protected from undesired enzymatic activities by a nucleoprotein complex called the telomere. Expanding evidence indicates that telomeres have central functions in human aging and tumorigenesis. While it is undoubtedly important to follow current advances in telomere biology, it is also fruitful to be well informed in seminal historical studies for a comprehensive understanding of telomere biology, and for the anticipation of future directions. With this in mind, I here summarize the early history of telomere biology and current advances in the field, mostly focusing on mammalian studies relevant to aging and cancer.

著者

Motohiro Akashi Shota Harada Syunsuke Moki Yuki Okouji Kiwamu Takahashi Shigeki Kada Keigo Yamagami Yasuhiko Sekine Satoru Watanabe Taku Chibazakura Hirofumi Yoshikawa

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.16-00071, (Released:2017-03-24)

被引用文献数

3

---

We developed an insertion sequence transposition detection system called the "jumping cat assay" and applied it to the Bacillus subtilis chromosome using IS256Bsu1 derived from B. subtilis natto. The high frequency of transposition enabled us to explore host factors; combining the assay and genetic analyses revealed that recA is essential for the transposition of IS256Bsu1. Detailed analyses using various domain mutants of recA demonstrated that this essentiality is not related to the function of recA in homologous recombination. Instead, the ATP binding and hydrolysis function seemed to be crucial for IS transposition. To elucidate the role of recA, we focused on the muB gene of the enterobacteriophage Mu. Based on information from the NCBI Conserved Domain Database, both MuB and RecA belong to the P-loop dNTPase superfamily. Further experiments revealed that muB complements the transposition-defective phenotype of a recA deletant, although it could not rescue UV sensitivity. These results suggest that recA shares a common function with muB that helps the transposition of IS256Bsu1 in B. subtilis.

著者

Abbasali Emamjomeh Bahram Goliaei Ali Torkamani Reza Ebrahimpour Nima Mohammadi Ahmad Parsian

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.89, no.6, pp.259-272, 2014-12-01 (Released:2015-05-02)

参考文献数

70

被引用文献数

7

---

Protein-protein interactions (PPIs) are highly important because of their main role in cellular processes and biochemical pathways; therefore, PPI can be very useful in the prediction of protein functions. Experimental techniques of PPI detection have certain drawbacks; hence computational methods can be used to complement wet lab techniques. Such methods can be applied to PPI prediction as well as validation of experimental results. Computational algorithms can lead to many false PPI predictions, which in turn result in non-adequate performance. We have developed a novel method based on combined analysis, entitled PPIccc. Three different descriptors for PPIccc included gene co-expression values, codon usage similarity and conservation of surface residues between protein products of a gene pair, which combined to predict PPI. Validation of results based on Human Protein Reference Database (HPRD) indicated improvement of performance in our proposed method. The results also revealed that conservation of surface residues between proteins in combination with codon usage similarity of their related genes increase the performance of PPI prediction. This means that codon usage similarity and surface residues between proteins (only sequence-based features) can predict PPIs as good as PPIccc.

著者

Satoshi Ishishita Yoichi Matsuda

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.91, no.2, pp.63-75, 2016-04-01 (Released:2016-10-13)

参考文献数

144

被引用文献数

6

---

Hybrid incompatibility is important in speciation as it prevents gene flow between closely related populations. Reduced fitness from hybrid incompatibility may also reinforce prezygotic reproductive isolation between sympatric populations. However, the genetic and developmental basis of hybrid incompatibility in higher vertebrates remains poorly understood. Mammals and birds, both amniotes, have similar developmental processes, but marked differences in development such as the XY/ZW sex determination systems and the presence or absence of genomic imprinting. Here, we review the sterile phenotype of hybrids between the Phodopus dwarf hamsters P. campbelli and P. sungorus, and the inviable phenotype of hybrids between two birds of the family Phasianidae, chicken (Gallus gallus domesticus) and Japanese quail (Coturnix japonica). We propose hypotheses for developmental defects that are associated with these hybrid incompatibilities. In addition, we discuss the genetic and developmental basis for these defects in conjunction with recent findings from mouse and avian models of genetics, reproductive biology and genomics. We suggest that these hybrids are ideal animal models for studying the genetic and developmental basis of hybrid incompatibility in amniotes.

著者

Hideo Hatase Ryusuke Sudo Kunihiro K. Watanabe Takashi Kasugai Tomomi Saito Hitoshi Okamoto Itaru Uchida Katsumi Tsukamoto

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.83, no.5, pp.423-426, 2008 (Released:2009-01-24)

参考文献数

19

被引用文献数

8 19

---

We verified whether telomere length shortens with age in the loggerhead sea turtle (Caretta caretta) by measuring telomere lengths (relative telomere to single copy gene [T/S] ratios) in whole blood and epidermis from 20 captive individuals with a real-time PCR method. There was no significant correlation between age and relative T/S ratios in blood. Although the correlation between age and relative T/S ratios in epidermis was not significant, older turtles had smaller relative T/S ratios in epidermis. It was thus demonstrated that telomere length in epidermis could be a useful age estimator for sea turtles. Relative age information obtained with this simple, rapid, non-invasive technique may help to advance our understanding of the ecology of endangered sea turtles. This is the first publication on age-related changes in telomere length among chelonians.

著者

Saki Sunaga Noriyoshi Akiyama Ryutaro Miyagi Aya Takahashi

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.15-00061, (Released:2016-03-25)

被引用文献数

3

---

Molecular mechanisms underlying standing genetic variation of an ecologically relevant trait such as pigmentation trait variation in a model insect, Drosophila melanogaster, are relevant to our understanding of different kinds of intergenomic interactions. In this study, we focused on the association between body pigmentation and stress resistance, and on genotype-by-environment interaction, both of which are likely to contribute to the persistence of phenotypic variation in a natural population. First, we detected a significant association between pigmentation traits in females and starvation resistance (darker strains were weaker) and a weak association between pigmentation and chill coma recovery time (darker strains showed shorter recovery time) among 20 inbred strains from the Drosophila melanogaster Genetic Reference Panel (DGRP), which originated from a natural population in North America. These associations revealed a complex relationship between body pigmentation and physiological traits that may give rise to balanced selective forces acting on the traits under fluctuating environmental conditions. Second, using four of the DGRP strains, a substantial degree of genotype (strain) × environment (rearing temperature) interaction was detected among expression levels of the genes encoding effector enzymes in the melanin biosynthesis pathway. These interactions can potentially reduce the efficiency of purifying selection on the pigmentation traits over a wide range of temperature conditions. Finally, we discuss possible mechanisms that contribute to the maintenance of the standing pigmentation variation in this species.

著者

Naohiko T. Miyashita

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.90, no.2, pp.61-77, 2015-04-01 (Released:2015-09-18)

参考文献数

50

被引用文献数

9 28

---

Soil bacterial community structures of six dominant phyla (Acidobacteria, Proteobacteria, Verrucomicrobia, Planctomycetes, Bacteroidetes and Actinobacteria) and unclassified bacteria detected in tropical Sarawakian and temperate Japanese forests were compared based on 16S rRNA gene sequence variation. The class composition in each phylum was similar among the studied forests; however, significant heterogeneities of class frequencies were detected. Acidobacteria and Proteobacteria were the most dominant phyla in all six forests, but differed in the level of bacterial species diversity, pattern of species occurrence and association pattern of species composition with physicochemical properties in soil. Species diversity among Acidobacteria was approximately half that among Proteobacteria, based on the number of clusters and the Chao1 index, even though a similar number of sequence reads were obtained for these two phyla. In contrast, species diversity within Planctomycetes and Bacteroidetes was nearly as high as within Acidobacteria, despite many fewer sequence reads. The density of species (the number of sequence reads per cluster) correlated negatively with species diversity, and species density within Acidobacteria was approximately twice that within Proteobacteria. Although the percentage of forest-specific species was high for all bacterial groups, sampling site-specific species varied among bacterial groups, indicating limited inter-forest migration and differential movement of bacteria in forest soil. For five of the seven bacterial groups, including Acidobacteria, soil pH appeared to strongly influence species composition, but this association was not observed for Proteobacterial species. Topology of UPGMA trees and pattern of NMDS plots among the forests differed among the bacterial groups, suggesting that each bacterial group has adapted and evolved independently in each forest.

著者

Takashi Yasukawa Yasuyuki Nakahara Jun Hirai Yoshihiro H. Inoue

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.90, no.1, pp.11-20, 2015-02-01 (Released:2015-06-25)

参考文献数

62

被引用文献数

1 6

---

Reactive oxygen species (ROS) generated during energy production processes are a major cause of oxidative DNA damage. A DNA glycosylase encoded by the Ogg1 gene removes oxidized guanine bases and is widely conserved. However, the biological role of the gene in individual organisms has not yet been characterized in Drosophila, which is a suitable model to study the influence of oxidative damage on senescence. Here, we performed a genetic analysis to confirm that Ogg1 plays an essential role in the removal of 8-oxo-guanines from nuclei. We first confirmed by quantitative real-time PCR that Ogg1 mRNA expression was reduced by 30–55% in Ogg1 mutants and in flies expressing inducible Ogg1 dsRNA compared to control flies. We then showed that additional accumulation of 8-oxo-guanines occurred in the nuclei of epithelial midgut cells after paraquat feeding in flies with downregulated Ogg1 expression. We confirmed that a transposon possessing the UAS sequence was integrated in the 5′-UTR of the Ogg1 alleles and that it is oriented in the same transcriptional direction as the gene. Using the Gal4/UAS system, which enables us to induce ectopic expression in Drosophila, we induced overexpression of Ogg1 by 40-fold. We observed a lower amount of 8-oxo-guanine in the midgut epithelial cells of adults overexpressing Ogg1. These genetic data strongly suggest that the Drosophila Ogg1 ortholog CG1795 plays an essential role in the suppression of 8-oxo-guanines, consistent with its role in other organisms. Although adult flies with reduced Ogg1 expression failed to show elevated sensitivity to paraquat, those with Ogg1 overexpression showed resistance to oxidative stress by paraquat feeding and had a significantly longer lifespan in normal feeding conditions. These observations are consistent with the hypothesis that oxidative DNA damage by ROS accumulation is a major contributor to senescence.

著者

Dhananjoy S. Chingangbam Joykumar M. Laishram Hitoshi Suzuki

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.90, no.1, pp.21-30, 2015-02-01 (Released:2015-06-25)

参考文献数

42

被引用文献数

3 5

---

The Indian subcontinent and Southeast Asia are hotspots of murine biodiversity, but no species from the Arakan Mountain system that demarcates the border between the two areas has been subjected to molecular phylogenetic analyses. We examined the mitochondrial cytochrome b gene sequences in six murine species (the Rattus rattus species complex, R. norvegicus, R. nitidus, Berylmys manipulus, Niviventer sp. and Mus musculus) from Manipur, which is located at the western foot of the mountain range. The sequences of B. manipulus and Niviventer sp. examined here were distinct from available congeneric sequences in the databases, with sequence divergences of 10–15%. Substantial degrees of intrapopulation divergence were detected in R. nitidus and the R. rattus species complex from Manipur, implying ancient habitation of the species in this region, while the recent introduction by modern and prehistoric human activities was suggested for R. norvegicus and M. musculus, respectively. In the nuclear gene Mc1r, also analyzed here, the R. rattus species complex from Manipur was shown to possess allelic sequences related to those from the Indian subcontinent in addition to those from East Asia. These results not only fill gaps in the phylogenetic knowledge of each taxon examined but also provide valuable insight to better understand the biogeographic importance of the Arakan Mountain system in generating the species and genetic diversity of murine rodents.

著者

Koichiro Tsunewaki Naoki Mori Shigeo Takumi

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.89, no.5, pp.195-202, 2014-10-01 (Released:2015-04-02)

参考文献数

19

被引用文献数

2

---

In the course of reconstructing Aegilops caudata from its own genome (CC) and its plasmon, which had passed half a century in common wheat (genome AABBDD), we produced alloplasmic Ae. cylindrica (genome CCDD) with the plasmon of Ae. caudata. This line, designated (caudata)-CCDD, was found to express male sterility in its second substitution backcross generation (SB2) of (caudata)-AABBCCDD pollinated three times with the Ae. cylindrica pollen. We repeatedly backcrossed these SB2 plants with the Ae. cylindrica pollen until the SB5 generation, and SB5F2 progeny were produced by self-pollination of the SB5 plants. Thirteen morphological and physiological characters, including pollen and seed fertilities, of the (caudata)-CCDD SB5F2 were compared with those of the euplasmic Ae. cylindrica. The results indicated that the male sterility expressed by (caudata)-CCDD was due to genetic incompatibility between the Ae. cylindrica genome and Ae. caudata plasmon that did not affect any other characters of Ae. cylindrica. Also, we report that the genome integrity functions in keeping the univalent transmission rate high.

著者

Yoshiyuki Suzuki Yuki Kobayashi Masayuki Horie Keizo Tomonaga

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.89, no.3, pp.143-148, 2014-06-01 (Released:2014-12-04)

参考文献数

46

被引用文献数

1 12

---

Endogenous bornavirus-like nucleoprotein (EBLN) elements are nucleotide sequences homologous to the bornavirus N gene that have been identified in animal genomes. EBLN elements are considered to have been generated through reverse transcription of bornavirus N mRNA, mainly with the aid of long interspersed element-1 (LINE-1). The genome of thirteen-lined ground squirrels (Ictidomys tridecemlineatus) contains an EBLN element, itEBLN, which is thought to have been integrated less than 8.5 million years ago (MYA). However, it was also reported that the LINE-1 activity on this lineage was lost 4-5 MYA. Here, molecular evolutionary analyses were conducted to gain insights into the integration time of itEBLN. In a phylogenetic analysis of bornavirus N and itEBLN, using an EBLN element from cape golden moles (Chrysochloris asiatica) (caEBLN) as the outgroup, the integration time of itEBLN appeared to be close to the time of the most recent common ancestor (MRCA) for bornavirus N. From an analysis of genomic sequences for bornavirus strains isolated at different time points, the time of the MRCA for bornavirus N was estimated to be < 0.3 MYA. These results suggest that the integration time of itEBLN was much later than the loss of LINE-1 activity, supporting the non-LINE-1-mediated integration of itEBLN.

著者

Shu Kondo

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.89, no.1, pp.3-8, 2014 (Released:2014-05-10)

参考文献数

41

被引用文献数

7 17

---

Drosophila melanogaster has the longest history as a genetic model system and even in the present day remains the front runner in diverse fields of biology. However, lack of a convenient method to make specified modifications to endogenous genes has been a pain in the neck for many fly geneticists for decades. Synthetic nuclease technologies, especially the CRISPR/Cas9 system, hold great promise for a breakthrough. Synthetic nucleases are programmable nucleases that can be directed to cleave a specified sequence in the genome. Deleterious mutations can be efficiently induced by expression of a synthetic nuclease that targets a gene of interest. Precise modification of the target site, such as a reporter gene knock-in, is also possible by simultaneous delivery of a synthetic nuclease and a targeting vector. Here I summarize recent advances in synthetic nuclease technologies and discuss their possible applications to Drosophila genetics.

著者

Yusaku Yasuno Yoshihiro H. Inoue Masa-Toshi Yamamoto

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.2, pp.113-126, 2013 (Released:2013-07-06)

参考文献数

40

被引用文献数

3

---

Sex ratio distortion, which is commonly abbreviated as sex-ratio, has been studied in many Drosophila species, but the mechanism remains largely unknown. Here, we report on the sex-ratio mutant of D. simulans named excess of females (exf). The third chromosomal recessive mutation results in a sex ratio of approximately 0.2 or less (males/total). Cytological observation demonstrated that meiosis appeared to be completed normally, but that most Y chromosome-bearing nuclei failed to elongate during spermiogenesis, as revealed by fluorescence in situ hybridization using sex chromosome-specific probes. These aberrant nuclei contained membranous inclusions as revealed by electron microscopic analysis. Most of the aberrant exf spermatids failed to individualize and mature, suggesting that a later stage of spermiogenesis is involved in prevention of production of sperm with abnormal morphology. On the one hand, in exf seminal vesicles, sperm nuclei with a length of 5–8.5 μm were occasionally observed, in addition to those with wild-type sperm dimensions, that is, a length of approximately 10 μm. Thus, spermatids with less severe nuclear defects can escape elimination and be released into the seminal vesicles as mature sperm. Furthermore, we constructed His2AvD-GFP and ProtamineB-eGFP transgenic lines in D. simulans, and examined the processes involved in replacement of chromatin proteins over a time course, according to nuclear morphology. We found that both normal and abnormal sperm heads demonstrated equal chromatin replacement during late spermiogenesis. Our results suggest that exf belongs to a unique class of meiotic drive systems in that (1) intranuclear membranous inclusions cause failure of nuclear shaping of Y-bearing spermatids without affecting the histone-protamine transition, and (2) a portion of the aberrant spermatids differentiate into mature sperm; these are transferred to and stored by females.

著者

Kuniaki Saito

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.1, pp.9-17, 2013 (Released:2013-05-14)

参考文献数

76

被引用文献数

8 28

---

A mechanism is required to repress the expression and transposition of transposable elements (TEs) to ensure the stable inheritance of genomic information. Accumulating evidence indicates that small non-coding RNAs are important regulators of TEs. Among small non-coding RNAs, PIWI-interacting RNAs (piRNAs) serve as guide molecules for recognizing and silencing numerous TEs and work in collaboration with PIWI subfamily proteins in gonadal cells. Disruption of the piRNA pathway correlates with loss of proper genomic organization, gene expression control and fertility. Moreover, recent studies on the molecular mechanisms of piRNA biogenesis and on piRNA function have shown that piRNAs act as maternally inherited genic elements, transferring information about repressed TEs to progeny. These findings enable a molecular explanation of mysterious epigenetic phenomena, such as hybrid dysgenesis and TE adaptation with age. Here, I review our current knowledge of piRNAs derived from biochemical and genetic studies and discuss how small RNAs are utilized to maintain genome organization and to provide non-DNA genetic information. I mainly focus on Drosophila but also discuss comparisons with other species.

著者

Takashi Kitano Norimasa Matsuoka Naruya Saitou

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.72, no.1, pp.25-34, 1997 (Released:2002-11-26)

参考文献数

30

被引用文献数

13 16

---

The phylogenetic relationship among the salmonid fishes of the genus Oncorhynchus has been analyzed using various kinds of markers for a long time. However, there are three major disagreements among those studies; (1) the authenticity of the Pacific salmon group as a monophyletic cluster, (2) the phylogenetic relationship among three Pacific salmons (pink salmon, sockeye salmon, and chum salmon), and (3) the phylogenetic position of masu salmon. We used allozyme electrophoresis to clarify the phylogenetic relationship between the Pacific salmon group and the Pacific trout group. Furthermore, we reanalysed published mitochondrial DNA D-loop sequences (Shedlock et al., 1992). Allozymic data and mtDNA data indicated the following consistent results; (1) all Pacific salmons formed a monophyletic cluster, (2) chum salmon and pink salmon were clustered within those Pacific salmons, (3) masu salmon formed a cluster with other Pacific salmons and diverged first in this group.

著者

Sachiko Tomioka Toshiro Aigaki Takashi Matsuo

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.87, no.5, pp.323-329, 2012 (Released:2013-02-13)

参考文献数

13

被引用文献数

2 7

---

Insect odorant-binding proteins function in the sensing of odors, tastes, and pheromones. Genes encoding two odorant-binding proteins, Obp57d and Obp57e, were identified to be involved in the behavioral adaptation of Drosophila sechellia to its host plant. The two genes are expressed in cells associated with taste sensilla on the legs, and the expression pattern in the legs is conserved among closely related species. To identify the cis-regulatory elements necessary for the expression in the leg sensilla, the promoter sequences of Obp57d and Obp57e were compared among species. Two types of conserved sequence-motifs were found as candidate cis-regulatory elements. Functions of these conserved elements in the promoters of D. melanogaster Obp57d and Obp57e were examined by using a newly constructed vector that combines the advantages of φC31 integrase-based transformation and gypsy transposable-element-derived insulators. By GFP-reporter assay using the new vector, it was confirmed that these conserved elements are necessary for the expression in the legs, working synergistically with each other to affect the expression level. Single-nucleotide substitutions in these elements dramatically changed the promoter activity. These results provide insight into the molecular mechanism for evolution of adaptive behavior via modulation of OBP expression levels.

著者

Kanako Kawaura Asuka Saeki Takehiro Masumura Shigeto Morita Yasunari Ogihara

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.86, no.4, pp.249-255, 2011 (Released:2011-12-29)

参考文献数

23

被引用文献数

3 8 2

---

The plant chondriome confers a complex nature. The atp4 gene (formerly called orf25) of Aegilops crassa (CR) harbors the promoter sequence of the rps7 gene from common wheat (Triticum aestivum cv. Chinese Spring, CS). The rps7 gene of CR has the promoter sequence of CS atp6. The atp6 gene of CR contains an unknown sequence inside of its coding region. Since repeat sequences have been found around the breaking points, these structural alterations are most likely generated through homologous recombination. In this study, PCR analysis was performed to detect structural alterations in each of three lines: euplasmic lines of Ae. crassa, Chinese Spring, and alloplasmic Chinese Spring wheat with the cytoplasm of Ae. crassa ((cr)-CS). We found that each of these lines contained both genotypes, although mitochondrial genotypes of CR in Chinese Spring wheat and CS genotypes in Ae. crassa were still retained as minor fractions (less than 10%). On the other hand, CS mitochondrial gene frequencies in ((cr)-CS) were shown to be ca. 30%. SNP analysis after DNA sequencing of these genes indicated that minor types of all three mitochondrial genes in alloplasmic wheat contained the mitochondrial gene types from pollens. Since the frequencies of paternal mitochondrial gene types in F1 were about 20%, successive backcrossing increased the frequencies of paternal mitochondrial gene types to around 30% in alloplasmic wheat. Expression profiles of these mitochondrial genes were quantitatively analyzed by RT-PCR. Transcripts of paternal mitochondrial gene types were scarcely found. This suggests that minor fractions including paternal mitochondrial gene types are maintained and silenced in the descendants.