Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2019 Jun 11;116(24):11845-11850. doi: 10.1073/pnas.1817373116. Epub 2019 Apr 29.

Germline-restricted chromosome (GRC) is widespread among songbirds.

Author information

1
Institute of Cytology and Genetics, Russian Academy of Sciences, Siberian Department, 630090 Novosibirsk, Russia.
2
Department of Cytology and Genetics, Novosibirsk State University, 630090 Novosibirsk, Russia.
3
SibEcoCenter LLC, 630009 Novosibirsk, Russia.
4
Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia.
5
Institute of Cytology and Genetics, Russian Academy of Sciences, Siberian Department, 630090 Novosibirsk, Russia; dmlarkin@gmail.com borodin@bionet.nsc.ru.
6
Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, NW1 0TU London, United Kingdom.

Abstract

An unusual supernumerary chromosome has been reported for two related avian species, the zebra and Bengalese finches. This large, germline-restricted chromosome (GRC) is eliminated from somatic cells and spermatids and transmitted via oocytes only. Its origin, distribution among avian lineages, and function were mostly unknown so far. Using immunolocalization of key meiotic proteins, we found that GRCs of varying size and genetic content are present in all 16 songbird species investigated and absent from germline genomes of all eight examined bird species from other avian orders. Results of fluorescent in situ hybridization of microdissected GRC probes and their sequencing indicate that GRCs show little homology between songbird species and contain a variety of repetitive elements and unique sequences with paralogs in the somatic genome. Our data suggest that the GRC evolved in the common ancestor of all songbirds and underwent significant changes in the extant descendant lineages.

KEYWORDS:

Passeriformes; avian genome; chromosome evolution; meiosis; programmed DNA elimination

PMID:
31036668
PMCID:
PMC6575587
[Available on 2019-10-29]
DOI:
10.1073/pnas.1817373116

Conflict of interest statement

The authors declare no conflict of interest.

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center