Published Papers - Ken Sahara

Feminizing Wolbachia endosymbiont disrupts maternal sex chromosome inheritance in a butterfly species.

Kageyama D, Ohno M, Sasaki T, Yoshido A, Konagaya T, Jouraku A, Kuwazaki S, Kanamori H, Katayose Y, Narita S, Miyata M, Riegler M, Sahara K

Evolution Letters   1 ( 5 ) 232 - 244   2017.10  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

(2017): 1(5): 232-244.

Relative humidity and maintenance of p50 silkworms reared on artificial diet.

Yuri K, Sahara K

Journal of Insect Biotechnology and Sericology   86   43 - 47   2017.04  [Refereed]

International Conference Proceedings  Multiple authorship

A history of chromosome identification in Bombyx mori

Ken Sahara, Atsuo Yoshido, Yuji Yasukochi

Chromosome Science   19   3 - 9   2017.04  [Refereed]

International Conference Proceedings  Multiple authorship

Variation in nesting behavior of eight species of spider mites, Stigmaeopsis having sociality

Yutaka Saito, Yan-Xuan Zhang, Kotaro Mori, Katsura Ito, Yukie Sato, Anthony R. Chittenden, Jian-Zhen Lin, Younghae Chae, Takane Sakagami, Ken Sahara

Science of Nature   103   87   2016.10  [Refereed]

Academic Journal  Multiple authorship

Fissions, fusions, and translocations shaped the karyotype and multiple sex chromosome constitution of the northeast-Asian wood white butterfly, Leptidea amurensis

JINDRA SICHOVA, MIZUKI OHNO, VLAD DINCA, MICHIHITO WATANABE, KEN SAHARA, FRANTISEK MAREC

Biological Journal of the Linnean Society   118   457 - 471   2016.05  [Refereed]

Academic Journal  Multiple authorship

The fate of W chromosomes in hybrids between wild silkmoths, Samia cynthia ssp.: no role in sex determination and reproduction

A Yoshido, F Marec, K Sahara

Heredity   116   424 - 433   2016.04  [Refereed]

Academic Journal  Multiple authorship

XX/XY System of Sex Determination in the Geophilomorph Centipede Strigamia maritima

Jack E. Green, Martina Dalíková, Ken Sahara, František Marec, Michael Akam

PLoSONE   11 ( 2 ) e0150292   2016.02  [Refereed]

Academic Journal  Multiple authorship

DOI

Mapping and recombination analysis of two moth colour mutations, Black moth and Wild wing spot, in the silkworm Bombyx mori.

Ito K, Katsuma S, Kuwazaki S, Jouraku A, Fujimoto T, Sahara K, Yasukochi Y, Yamamoto K, Tabunoki H, Yokoyama T, Kadono-Okuda K, Shimada T

Heredity   116   52 - 59   2016.01  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

A FISH-based chromosome map for the European corn borer yields insights into ancient chromosomal fusions in the silkworm.

Yasukochi Y, Ohno M, Shibata F, Jouraku A, Nakano R, Ishikawa Y, Sahara K

Heredity   116   75 - 83   2016.01  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

(2016): Heredity 116, 75-83

Dynamic karyotype evolution and unique sex determination systems in Leptidea wood white butterflies.

Šíchová J, Voleníková A, Dincă V, Nguyen P, Vila R, Sahara K, Marec F

BMC Evolutionary Biology   15 ( 89 )   2015.05  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

A new molecular technique for determining the sex of Harmonia axyridis.

Gotoh H, Nishikawa H, Sahara K, Yaginuma T, Niimi T

Journal of Insect Biotechnology and Sericology   84   9 - 15   2015.02  [Refereed]

International Conference Proceedings  Multiple authorship

We have developed a fast and efficient PCR-based technique to sex all developmental stages of the ladybird beetle Harmonia axyridis. Previously, we established a male-specific fluorescent expressing strain of H. axyridis with the piggyBac vector. FISH analyses revealed that the transgene inserted into the H. axyridis genome in the male Y-chromosome. Because only males expressed the fluorescent signal, we were able to differentiate between the sexes of this transgenic strain even in newly hatched larvae. We took advantage of this insertion and designed an inverse PCR reaction and genome walking surrounding the inserted region to identify 3,781 bp of the male Y-chromosome genomic sequence. From this male specific region, we designed a PCR-based protocol to identify sexes from all H. axyridis developmental stages.

FISH identification of Helicoverpa armigera and Mamestra brassicae chromosomes by BAC and fosmid probes.

Sahara K , Yoshido A, Shibata F, Fujikawa N, Okabe T, Tanaka-Okuyama M, Yasukochi Y

Insect Biochemistry and Molecular Biology   in press   2013.04  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

Neo-sex chromosomes and adaptive potential in tortricid pests.

Nguyen P, Sýkorová M, Šíchová J, Kůta V, Dalíková M, Čapková Frydrychová R, Neven LG, Sahara K, Marec F

The Proceedings National Academy of Sciences USA   110   6931 - 6936   2013.04  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

Rapid turnover of the W chromosome in geographical populations of wild silkmoths, Samia cynthia ssp.

Yoshido A, Šíchová J, Kubíčková S, Marec F, Sahara K

Chromosome Research   21   149 - 164   2013.04  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

EST sequencing and fosmid library construction in a non-model moth, Mamestra brassicae, for comparative mapping （訳）比較マッピングのための非モデルガ類のヨトウガにおけるEST配列決定とフォスミドライブラリー作製

Kamimura M, Taetishi K, Tanaka-Okuyama M, Okabe T, Shibata F, Sahara K, Yasukochi Y

Genome   in press   2012.10  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

ガとチョウ類のFISHを通じた比較ゲノム解析を進めるため、重要な農業害虫であるヨトウガのフォスミドライブラリーを作製し、EST配列の決定からカイコ単一遺伝子のオルソログを含むヨトウガフォスミドを120個特定した。この研究ではcDNAの行列プールを用いることでEST配列決定の効率化を実現した。一部のフォスミドを用いたFISH解析よりカイコとのシンテニーが示された。

Phenotypic grouping of 141 BmNPVs lacking viral gene sequences （訳）ウイルス遺伝子欠損による141BmNPV遺伝子の形質グルーピング

Ono C, Kamagata T, Taka H, Sahara K, Asano S, Bando H

Virus Research   165 ( 2 ) 197 - 206   2012.05  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

Sex chromosome evolution in moths and butterflies （訳）ガとチョウ類における性染色体進化

Sahara K, Yoshido A, Traut W

Chromosome Research   20 ( 1 ) 83 - 94   2011.12  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

ガとチョウの仲間である鱗翅目昆虫の雌へテロ型(WZ/ZZ)性染色体進化についての総説。FISHによる性染色体同定、性染色体の由来、性染色体構成の多様性、性決定、性染色体上の遺伝子、遺伝子量補正、性染色体工学による応用ならびに展望に関して我々の研究データを中心に概説してある。

Sex-linked pheromone receptor genes of the European corn borer, Ostrinia nubilalis, are in tandem arrays（訳）ヨーロッパアワノメイガのフェロモンレセプター遺伝子はZ染色体上にタンデムに並んでいる

Yasukochi Y, Miura N, Nakano R, Sahara K, Ishikawa Y

PLoS ONE   6 ( 4 ) e18843   2011.04  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

This is the first report of tandemly arrayed sex pheromone receptor genes in Lepidoptera. The localization of an OR gene cluster on the Z chromosome agrees with previous findings for a Z-linked locus responsible for O. nubilalis male behavioral response to sex pheromone. The 181-bp irect repeats might enhance gene duplications by unequal crossovers. An autosomal locus responsible for male esponse to sex pheromone in Heliothis virescens and H.subflexa was recently reported to contain at least four OR genes. Taken together, these findings support the hypothesis that eneration of additional copies of OR genes can increase the potential for male moths to acquire altered specificity for pheromone components, and accordingly, facilitate differentiation of sex pheromones.

Samia cynthia versus Bombyx mori: Comparative gene mapping between a species with a low-number karyotype and the model species of Lepidoptera. （訳）シンジュサン対カイコ:鱗翅目昆虫における染色体数の少ない種とモデル種の比較遺伝子マッピング

Yoshido A, Yasukochi Y, Sahara K

Insect Biochemistry and Molecular Biology   41   370 - 377   2011.03  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

We performed gene-based comparative FISH mapping between a wild silkmoth, Samia cynthia ssp. with a low number of chromosomes (2n=25-28) and the model species, Bombyx mori (2n=56), in order to identify the genomic components that make up the chromosomes in a low-number karyotype. Mapping
of 64 fosmid probes containing orthologs of B. mori genes revealed that the homologues of either two or four B. mori chromosomes constitute the S. c. ricini (Vietnam opulation, 2n=27/28, Z0/ZZ) autosomes. Where tested, even the gene order was conserved between S. c. ricini and B. mori. This was also true for the originally autosomal parts of the neo-sex chromosomes in S. c. walkeri (Sapporo population, 2n=26/26, neo-Wneo-Z/neo-Zneo-Z) and S. cynthia subsp. indet. (Nagano population, 2n=25/26, neo-WZ1Z2/Z1Z1Z2Z2). The results are evidence for an internal stability of lepidopteran chromosomes even when all autosomes had undergone fusion processes to form a low-number karyotype.

Isolation of BAC clones containing conserved genes from libraries of three distantly related moths: A useful resource for comparative genomics of Lepidoptera. （訳）3種の遠縁なガ類における保存遺伝子を含むBACの単離: 鱗翅目昆虫における比較ゲノム解析に利用可能なリソース

Yasukochi Y, Tanaka-Okuyama M, Kamimura M, Nakano R, Naito Y, Ishikawa Y, Sahara K

Journal of Biomedicine and Biotechnology   ID 165894   2010.11  [Refereed]

Bulletin of University, Institute, etc.  Multiple authorship

Lepidoptera, butterflies and moths, is the second largest animal order and includes numerous agricultural pests. To facilitate　comparative genomics in Lepidoptera, we isolated BAC clones containing conserved and putative single-copy genes from libraries　of three pests, Heliothis virescens, Ostrinia nubilalis, and Plutella xylostella, harboring the haploid chromosome number, n = 31, which are not closely related with each other or with the silkworm, Bombyx mori, (n = 28), the sequenced model lepidopteran.
A total of 108–184 clones representing 101–182 conserved genes were isolated for each species. For 79 genes, clones were isolated from more than two species, which will be useful as common markers for analysis using fluorescence in situ hybridization (FISH), as well as for comparison of genome sequence among multiple species.