Extraordinary centromeres: differences in the meiotic chromosomes of two rock lizards species Darevskia portschinskii and Darevskia raddei

PeerJ

article

Victor Spangenberg¹  Marine Arakelyan²  Eduard Galoyan³  Mark Pankin¹  Ruzanna Petrosyan²  Ilona Stepanyan⁴  Tatiana Grishaeva¹  Felix Danielyan²  Oxana Kolomiets¹ 

[1] Vavilov Institute of General Genetics;Department of Zoology, Yerevan State University;Zoological Museum, Moscow State University;Scientific Center of Zoology and Hydroecology

关键词: Darevskia lizards;    Synaptonemal complex;    Dicentric chromosomes;    Reticulate evolution;    Neocentromere;    Meiosis;   

DOI  :  10.7717/peerj.6360

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

According to the synthesis of 30 years of multidisciplinary studies, parthenogenetic species of rock lizards of genus Darevskia were formed as a result of different combination patterns of interspecific hybridization of the four bisexual parental species: Darevskia raddei, D. mixta, D. valentini, and D. portschinskii. In particular, D. portschinskii and D. raddei are considered as the parental species for the parthenogenetic species D. rostombekowi. Here for the first time, we present the result of comparative immunocytochemical study of primary spermatocyte nuclei spreads from the leptotene to diplotene stages of meiotic prophase I in two species: D. portschinskii and D. raddei. We observed similar chromosome lengths for both synaptonemal complex (SC) karyotypes as well as a similar number of crossing over sites. However, unexpected differences in the number and distribution of anti-centromere antibody (ACA) foci were detected in the SC structure of bivalents of the two species. In all examined D. portschinskii spermatocyte nuclei, one immunostained centromere focus was detected per SC bivalent. In contrast, in almost every studied D. raddei nuclei we identified three to nine SCs with additional immunostained ACA foci per SC bivalent. Thus, the obtained results allow us to identify species-specific karyotype features, previously not been detected using conventional mitotic chromosome analysis. Presumably the additional centromere foci are result of epigenetic chromatin modifications. We assume that this characteristic of the D. raddei karyotype could represent useful marker for the future studies of parthenogenetic species hybrid karyotypes related to D. raddei.

【 授权许可】

CC BY