Aberrant meioses in diploid and triploid progeny of gynogenetic diploids produced from eggs of natural tetraploid loach, Misgurnus anguillicaudatus

Title:

Aberrant meioses in diploid and triploid progeny of gynogenetic diploids produced from eggs of natural tetraploid loach, Misgurnus anguillicaudatus

Creator:

Zhang, Quanqi, Hanada, Kumiko, and Arai, Katsutoshi

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:eb9d7e8d-45e9-856b-2a73-4d7d2cd75164
uuid:eb9d7e8d-45e9-856b-2a73-4d7d2cd75164

Subject:

polyploid, gynogenesis, and univalent

Type:

article and TEXT

Description:

Gynogenetic diploids were produced from the eggs of natural tetraploid loach Misgurnus anguillicaudatus (Pisces: Cobitidae) without any manipulation for chromosome duplication. When eggs of a four-year-old diploid gynogenetic individual were fertilized with spermatozoa of specimens from normal diploid and natural tetraploid lines, viable diploid and triploid progeny were produced, respectively. Thus, egg nucleus of the diploid gynogen is haploid. In the gonads of diploid progeny, diploid (2n = 50) and tetraploid (4n = 100) mitotic metaphases were observed. The majority of oocytes (76%) showed regular 25 bivalents as in normal diploids, but the other 16% showed a few univalents. The remaining 8% exhibited about 50 bivalents, suggesting chromosome duplication by premeiotic endomitosis. In the testes, a few spermatocytes (6%) showed normal 25 bivalents, but 86% contained various number of univalents and the remaining 8% contained about 50 bivalents. No peaks of spermatozoa were identified in the testis by flow cytometry. In the triploid progeny, triploid (3n = 75) and hexaploid (6n = 150) mitotic metaphases were observed in both ovaries and testes. Most meiotic figures (about 90%) contained approximately 25 bivalents and 25 univalents in both sexes; the rest contained approximately 75 or more bivalents. Spermatozoa were not identified in the testis by flow cytometry. Thus, the diploid males between the diploid gynogens and common diploid, and both sexes of triploids between the diploid gynogens and tetraploid, show aberrant meioses such as frequent formation of univalents, but the diploid females seem to be less affected.

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/

Source:

Folia zoologica | 2002 Volume:51 | Number:2

Harvested from:

CDK

Metadata only:

false