Department of Molecular Biology and Genetics, Faculty of Art and Science, Nevşehir Hacı Bektaş Veli University, Nevşehir, Turkey.
J Insect Sci. 2019 Sep 1;19(5). doi: 10.1093/jisesa/iez086.
In this study, chromosomal characteristics of Eratigena agrestris (Agelenidae) were investigated for the first time. Karyotype features including diploid chromosome number, sex chromosome system, chromosome morphology, and meiotic behavior were obtained from specimens collected in two localities of Mediterranean region. A spreading method including dissection, hypotonization, fixation, and staining was used to prepare the chromosome slides. In a total, 10 adult males were used due to having high numbers of dividing cells. Cytogenetical results showed that the diploid chromosome number and sex chromosome system was 2n♂ = 42 (X1X20). The sex chromosomes were identified tentatively. All chromosomes were telocentric. Relative chromosome lengths of autosomal pairs ranged between 5.65 and 3.32%, and relative chromosome lengths of X1 and X2 were 5.33 and 4.19%, respectively. In the first meiotic division stages, bivalents usually had one chiasma, but some had two chiasmata. At the end of the meiosis, two kinds of nuclei, with or without sex chromosomes, have occurred. These results contribute to a better characterization of the Agelenidae cytogenetic.
本研究首次对沙蛛属（Agelenidae）的染色体特征进行了研究。从地中海地区两个地点采集的标本中获得了包括二倍体染色体数、性染色体系统、染色体形态和减数分裂行为在内的染色体特征。采用包括解剖、低渗、固定和染色的展开方法来制备染色体载玻片。总共使用了 10 只成年雄性，因为它们具有大量分裂细胞。细胞遗传学结果表明，二倍体染色体数和性染色体系统为 2n♂=42（X1X20）。性染色体被初步鉴定。所有染色体都是端着丝粒的。常染色体对的相对染色体长度范围在 5.65%至 3.32%之间，X1 和 X2 的相对染色体长度分别为 5.33%和 4.19%。在第一次减数分裂阶段，二价体通常有一个交叉，但有些有两个交叉。在减数分裂结束时，出现了两种核，一种有性染色体，另一种没有性染色体。这些结果有助于更好地描述 Agelenidae 的细胞遗传学。
