TY - JOUR

T1 - Germline-Restricted Chromosome (GRC) in Female and Male Meiosis of the Great Tit (Parus major, Linnaeus, 1758)

AU - Torgasheva, Anna

AU - Malinovskaya, Lyubov

AU - Zadesenets, Kira

AU - Shnaider, Elena

AU - Rubtsov, Nikolai

AU - Borodin, Pavel

N1 - Funding Information: The study was funded by Russian Foundation of Basic Researches, grant # 19-34-90118 and by Ministry of Science and Higher Education of the Russian Federation, grants # 0259-2021-0011 and # 2019-0546 (FSUS-2020-0040). Microscopy was carried out at the Core Facility for Microscopy of Biologic Objects, SB RAS, Novosibirsk, Russia (regulation no. 3054). Publisher Copyright: Copyright © 2021 Torgasheva, Malinovskaya, Zadesenets, Shnaider, Rubtsov and Borodin.

PY - 2021/10/25

Y1 - 2021/10/25

N2 - All songbirds studied so far have a germline-restricted chromosome (GRC), which is present in the germ cells and absent in the somatic cells. It shows a wide variation in size, morphology, and genetic content between the songbird species. In this paper, we analyzed GRC behavior in female and male meiosis of the great tit, using immunolocalization of meiotic proteins and FISH with GRC-derived DNA probes. We found that, despite dozens of million years of independent evolution, the great tit GRC displays a striking similarity with the GRCs of two species of martins and two species of estrildid finches examined earlier. It was usually present in two copies in females forming recombining bivalent and in one copy in males forming a condensed heterochromatic body with dotted-like axial elements of the synaptonemal complex. We observed mosaicism for the GRC copy number in the female and male great tit. This indicates that one of the GRC copies might be passively lost during premeiotic germ cell divisions. After the meiotic prophase, the GRC was ejected from most male germ cells. The reverse and interspecies FISH with GRC-specific microdissected DNA probes indicates that GRCs of the great tit, pale martin, and zebra finch differ substantially in their genetic content despite similarities in the meiotic behavior.

AB - All songbirds studied so far have a germline-restricted chromosome (GRC), which is present in the germ cells and absent in the somatic cells. It shows a wide variation in size, morphology, and genetic content between the songbird species. In this paper, we analyzed GRC behavior in female and male meiosis of the great tit, using immunolocalization of meiotic proteins and FISH with GRC-derived DNA probes. We found that, despite dozens of million years of independent evolution, the great tit GRC displays a striking similarity with the GRCs of two species of martins and two species of estrildid finches examined earlier. It was usually present in two copies in females forming recombining bivalent and in one copy in males forming a condensed heterochromatic body with dotted-like axial elements of the synaptonemal complex. We observed mosaicism for the GRC copy number in the female and male great tit. This indicates that one of the GRC copies might be passively lost during premeiotic germ cell divisions. After the meiotic prophase, the GRC was ejected from most male germ cells. The reverse and interspecies FISH with GRC-specific microdissected DNA probes indicates that GRCs of the great tit, pale martin, and zebra finch differ substantially in their genetic content despite similarities in the meiotic behavior.

KW - avian chromosomes

KW - crossing over

KW - MLH1

KW - programmed DNA elimination

KW - recombination

KW - SYCP3

KW - synaptonemal complex

UR - http://www.scopus.com/inward/record.url?scp=85118789191&partnerID=8YFLogxK

U2 - 10.3389/fgene.2021.768056

DO - 10.3389/fgene.2021.768056

M3 - Article

C2 - 34759962

AN - SCOPUS:85118789191

VL - 12

JO - Frontiers in Genetics

JF - Frontiers in Genetics

SN - 1664-8021

M1 - 768056

ER -