Chromosome studies in the red howler monkey, Alouatta seniculus stramineus (Platyrrhini, Primates): description of an X1X2Y1Y2/X1X1X2X2 sex-chromosome system and karyological comparisons with other subspecies.
Chromosome studies in the red howler monkey, Alouatta seniculus stramineus (Platyrrhini, Primates): description of an X1X2Y1Y2/X1X1X2X2 sex-chromosome system and karyological comparisons with other subspecies.
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红吼猴 Alouatta seniculus stramineus（扁鼻，灵长类动物）的染色体研究：X1X2Y1Y2/X1X1X2X2 性染色体系统的描述以及与其他亚种的核学比较。
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
H. Seuánez
中科院分区：
文献类型：
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作者：
M. Lima;H. Seuánez
在红吼猴Alouatta seniculus stramineus （2n = 47、48或49）中，二倍体染色体数目的变化是由于微染色体数目的不同。男性呈Y型；常染色体易位涉及个体双臂常染色体的短臂。因此，雄性的性染色体构成为X1X2Y1Y2，其中X1代表原始X染色体，X2代表双臂常染色体（7号），Y1代表Y；7p易位产物，Y2是7q的单中心同源物。在第一次减数分裂中，可以在精母细胞中观察到具有链状结构的四价体。女性的性染色体结构为X1X1X2X2。在第13对和第19对中观察到染色体异型现象，这是由于染色体中心周围反转，而在第19对中观察到染色体异型现象是由于组成异染色质的存在。微染色体在个体间数量不同，也是异色的。在单个染色体对（No. 10）的两个不同位置观察到No染色。对菌株A.s.和麦康奈尔利A.s.的比较表明，这两个亚种具有相同的二倍体染色体数目（47、48或49），这也是由于微染色体数目的不同，而且它们具有相似的性染色体构成。然而，它们的核型并不相同，但可以通过相互易位而相互衍生。进一步与文献中报道的其他针叶蝉亚种的比较表明，该分类单元在染色体上并不统一，并且根据其形态特征的分类标准被认为是亚种的种群之间发生了大量的染色体洗牌。
In the red howler monkey, Alouatta seniculus stramineus (2n = 47, 48, or 49), variations in diploid chromosome number are due to different numbers of microchromosomes. Males exhibit a Y;autosome translocation involving the short arm of an individual biarmed autosome. Consequently, the sex-chromosome constitution in the male is X1X2Y1Y2, with X1 representing the original X chromosome, X2 the biarmed autosome (No. 7), Y1 the Y;7p translocation product, and Y2 the acrocentric homolog of 7q. In the first meiotic division, a quadrivalent with a chain configuration can be observed in spermatocytes. Females have an X1X1X2X2 sex-chromosome constitution. Chromosome heteromorphisms were observed in pair 13, due to a pericentric inversion, and pair 19, due to the presence of constitutive heterochromatin. Microchromosomes, which varied in number between individuals, were also heterochromatic. NOR-staining was observed at two separate sites on a single chromosome pair (No. 10). A comparison of A.s. stramineus with A.s. macconnelli shows that these two subspecies have identical diploid chromosome numbers (47, 48, or 49), again due to a varying number of microchromosomes, and that they share a similar sex-chromosome constitution. Their karyotypes, however, are not identical, but can be derived from each other by a reciprocal translocation. Further comparisons with other A. seniculus subspecies reported in the literature indicate that this taxon is not karyologically uniform and that substantial chromosome shuffling has occurred between populations that have been considered to be subspecies by taxonomic criteria based on their morphometric attributes.