GENETIC CONTROL MECHANISMS OF SEX DETERMINATION IN ORYZIAS FISHES

Oryzias 鱼类性别决定的遗传控制机制

基本信息

批准号：
07660240
负责人：
HAMAGUCHI Satoshi
金额：
$ 1.34万
依托单位：
NIIGATA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07660240/
关键词：
Oryzias latipes Oryzias curvinotus Sex-determination Sex-differentiation Teleost Sex-Reversal Gene Interspecific Hybrid

项目摘要

(1) The medaka, Oryzias latipes has been demonstrated to have an XX female/XY male sex-determination system by the sex-linked inheritance of body color as well as by the progeny test of the artificially sex-reversed fish. It is still an open question, however, either the X or the Y has a definitive role in the sex determination process of this fish. In the present experiment, triploid fish were produced, and the relationship between the sex choromosome composition and the sex of the fish were examined. All XXX fish obtained were female, whereas XXY were male, suggesting that the gene (s) on the Y determines the sex differentiation of the fish into male (dominant-Y system).(2) The sex-determination system of Oryzias fishes except Oryzias latipes has not been clarified so far. We produced gynogenetic diploid fish of O.curvinotus and examined their sex from the histological observations on the gonads of juvenile fish. We obtained 13 gynogenetic homozygous fish, all of which were female, i … More ndication that O.curvinotus also has an XX*-XY* sex-determination system.(3) We examined the sex of the interspecific hybrids between inbred strains of O.curvinotus and O.latipes (HdrR and HNI strains, the former originated from the Southern Population and the latter from the Northern Population). All the interspecific hybrids between HdrR strain and O.curvinotus (X^<HdrR> Y^<O.curvlnotus>) were female fish develop ovaries. On the other hand, the cross between HNI strain and O.curvinotus yields offsprings of both sex, that is X^<HN1> Y^<O.curvinotus> were male. These results can be interpreted that the sex determining gene on Y chromosome (SDY) need some additional genetic factor (s) to determine the sex of the individual, and the SDY of O.curvinotus is incompatible to the factors of HdrR whereas compatible to those of HNI.We conducted genetic analysis between HNI and HdrR to identify the factors. F1 fish between HNI and HdrR were mated to O.curvinotus, and all the interspecific hybrid from these cross were female. Then, the fish from the cross between F1 fish and HNI were mated with O.curvinotus. All the offsprings were also female. These results indicates that not a few genetic factors can be involved in the sex determination of Oryzias fishes. Further genetic analysis is in progress. Less

(1)通过体色的伴性遗传以及人工性别反转鱼的后代测试，已证明青鳉Oryzias latipes具有XX雌性/XY雄性性别决定系统。然而，X 或 Y 在该鱼的性别决定过程中具有决定性作用，这是一个悬而未决的问题。在本实验中，产生了三倍体鱼，以及性染色体组成与性别决定之间的关系。对获得的所有 XXX 鱼进行了性别检查，而 XXY 是雄性，这表明 Y 上的基因决定了鱼的性别分化为雄性（显性 Y 系统）。（2）除Oryzias latipes外，其他鱼类的性别决定系统尚未阐明。我们制备了O.curvinotus雌核发育二倍体鱼，并通过对幼鱼性腺的组织学观察来检验其性别。我们获得了 13 条雌核发育纯合鱼，均为雌性，表明 O.curvinotus 也具有 XX*-XY* 性别决定系统。(3) 我们检查了近交系之间的种间杂种的性别。 O.curvinotus 和 O.latipes（HdrR 和 HNI 品系，前者源自南方种群，后者源自北方种群）。 HdrR 品系和 O.curvinotus 之间的杂交 (X^<HdrR> Y^<O.curvlnotus>) 是雌鱼发育出卵巢。另一方面，HNI 品系和 O.curvinotus 之间的杂交产生两种性别的后代，即 X。 ^<HN1> Y^<O.curvinotus> 是男性这些结果可以解释为 Y 染色体上的性别决定基因 (SDY) 需要一些额外的遗传因素来确定性别。 O.curvinotus 的 SDY 与 HdrR 的因素不相容，而与 HNI 的相容。我们对 HNI 和 HdrR 之间进行遗传分析，以确定 HNI 和 HdrR 之间的 F1 鱼与 O 交配的因素。 Curvinotus，并且这些杂交产生的所有种间杂种都是雌性。然后，F1 鱼与 HNI 杂交的鱼与 O.curvinotus 交配，所有后代也都是雌性。这些结果表明，不少遗传因素可能参与 Oryzias 鱼类的性别决定。