树鼩（Vandeleuria o. oleracea）独特的多条性染色体：X1和X2的鉴定

Unique multiple sex chromosomes of the tree mouse Vandeleuria o. oleracea: identification of X1 and X2.

作者信息

Raman R, Sharma T

出版信息

Heredity (Edinb). 1976 Dec;37(3):435-9. doi: 10.1038/hdy.1976.109.

DOI:10.1038/hdy.1976.109

Abstract

The tree mouse Vandeleuria o. oleracea has an odd diploid chromosome complement (2n = 29 female/male) accompanied by a unique multiple sex-chromosome mechanism (X1X2Ymale/X1X1X2female). In the present paper the sex chromosomes have been identified unequivocally with the help of G-banding and DNA replication patterns which confirm our earlier suggestion that the X1 is smaller in size than the simple mammalian X, and also that the combined sizes of the X1 and X2 (3-8 and 1-7 per cent respectively) approximate to the size of the conservative mammalian X (5 per cent). It is proposed that the mammalian X has attained a minimum functional size so that further reduction is not tolerated.

摘要

树鼩（Vandeleuria o. oleracea）具有奇特的二倍体染色体组成（雌性/雄性2n = 29），伴随着独特的多性染色体机制（雄性为X1X2Y，雌性为X1X1X2）。在本文中，借助G带和DNA复制模式明确鉴定了性染色体，这证实了我们之前的推测，即X1的大小比简单哺乳动物的X染色体小，而且X1和X2的组合大小（分别为3 - 8%和1 - 7%）接近保守哺乳动物X染色体的大小（5%）。有人提出，哺乳动物的X染色体已达到最小功能大小，因此无法再进一步缩小。