Bianchi N O, Bianchi M S, Pamilo P, Vidal-Rioja L, de la Chapelle A
IMBICE, C.C. 403, La Plata, Argentina.
J Mol Evol. 1992 Jan;34(1):54-61. doi: 10.1007/BF00163852.
Zinc finger-Y (Zfy) and zinc finger-X (Zfx) genes were analyzed by Southern blotting in male and female specimens of 10 species belonging to the oryzomyne-akodontine stock of Cricetidae rodents. DNA fragments were used as characters to construct a parsimony tree of the genes. Zfx and Zfy trees in general coincide with the evolutionary history of the taxa. Both trees show Oryzomys longicaudatus genes as the outgroup whereas Akodon xanthorrhinus genes are also distant from those of the other species. Oxymycterus rufus and Bolomys obscurus share related sequences, while genes from the other six Akodon species form a group of their own. It was found that 9 out of the 10 species analyzed show Zfy amplification in a range varying from 2 to 24 copies and with a pattern that is clade specific. The estimation of the average changes per character strongly suggests that Zfy has evolved more rapidly than Zfx; our estimates of the rate of nucleotide substitution are 4.6 times higher for Zfy than for Zfx.
采用Southern印迹法对仓鼠科稻鼠 - 阿科鼠类群10个物种的雄性和雌性样本中的锌指 - Y（Zfy）基因和锌指 - X（Zfx）基因进行了分析。以DNA片段作为特征构建了这些基因的简约树。Zfx和Zfy树总体上与分类单元的进化历史一致。两棵树均显示长尾稻鼠基因作为外类群，而黄鼻稻鼠基因也与其他物种的基因相距较远。红毛稻鼠和暗稻鼠共享相关序列，而其他六个稻鼠物种的基因则自成一组。研究发现，在所分析的10个物种中，有9个物种的Zfy基因存在扩增，拷贝数在2至24个之间变化，且具有特定分支的模式。每个特征平均变化的估计强烈表明Zfy的进化速度比Zfx快；我们估计Zfy的核苷酸替代率比Zfx高4.6倍。
