Key Laboratory of Protein Chemistry and Fish Developmental Biology of the Education Ministry of China, College of Life Sciences, Hunan Normal University, 36 Lu Shan Road, Yue Lu District, Changsha 410081, Hunan, People's Republic of China.
Key Laboratory of Protein Chemistry and Fish Developmental Biology of the Education Ministry of China, College of Life Sciences, Hunan Normal University, 36 Lu Shan Road, Yue Lu District, Changsha 410081, Hunan, People's Republic of China.
Anim Reprod Sci. 2014 Dec 10;151(1-2):61-70. doi: 10.1016/j.anireprosci.2014.09.012. Epub 2014 Sep 28.
Distant hybridization can combine together the genomes of different species, which leads to changes of the offspring in phenotypes and genotypes. In this study, we successfully establish a fertile hybrid lineage by intergeneric hybridization of female blunt snout bream (BSB, Megalobrama amblycephala) × male topmouth culter (TC, Culter alburnus) and investigate some important biological traits of this lineage including the morphological traits, chromosomal number, karyotype, DNA content, gonadal development, egg and milt yield, sperm shape and density, fertilization rate and early survival rate. The results show that: (1) the diploid and triploid hybrids coexist in F1 and only diploid hybrids are found in F2, in which the diploid hybrids of F1 and F2 possess 48 chromosomes with one chromosome set of BSB and one chromosome set of TC, and the triploid hybrids of F1 possess 72 chromosomes with two chromosome sets of BSB and one chromosome set of TC. (2) All the tested males and females of the diploid F1 and F2 hybrids have the normal gonadal development and produce mature sperm and egg, respectively, which are fertilized with each other to form F2 and F3 hybrids, respectively, and finally form a diploid hybrid lineage (F1-F3). (3) The good fertility of the F1 and F2 hybrids of female BSB × male TC potentially provides reproductive base to make the hybrid lineage propagate from one generation to another. The formation of the hybrid lineage (F1-F3) also provides an ideal model to research the reproductive rules of distant hybrid progeny.
远缘杂交可以将不同物种的基因组组合在一起，导致后代表型和基因型的变化。在这项研究中，我们通过雌性团头鲂（Megalobrama amblycephala）×雄性翘嘴红鲌（Culter alburnus）的属间杂交成功建立了一个可育的杂种系，并研究了该杂种系的一些重要生物学特性，包括形态特征、染色体数、核型、DNA 含量、性腺发育、卵子和精液产量、精子形态和密度、受精率和早期存活率。结果表明：（1）F1 代中存在二倍体和三倍体杂种，而 F2 代中仅发现二倍体杂种，其中 F1 和 F2 代的二倍体杂种具有 48 条染色体，一组来自团头鲂，一组来自翘嘴红鲌，而 F1 代的三倍体杂种具有 72 条染色体，两组来自团头鲂，一组来自翘嘴红鲌。（2）所有测试的 F1 和 F2 代二倍体杂种的雌雄个体均具有正常的性腺发育，并分别产生成熟的精子和卵子，它们相互受精形成 F2 和 F3 杂种，最终形成一个二倍体杂种系（F1-F3）。（3）雌性团头鲂×雄性翘嘴红鲌 F1 和 F2 杂种的良好繁殖力为该杂种系从一代传播到另一代提供了生殖基础。杂种系（F1-F3）的形成也为研究远缘杂交后代的生殖规律提供了理想的模型。
