B chromosome polymorphism in South American cichlid. Issue 1 (30th November 2018)

• Record Type: Journal Article
• Authors: Perazzo, Giselle Xavier; Noleto, Rafael Bueno; Vicari, Marcelo Ricardo; Gava, Adriana; Cestari, Marta Margarete
• Is Part Of: Neotropical biodiversity. Volume 4:Issue 1(2018)
• Page Start: 3
• Page End: 9
• Publication Date: 2018-11-30
• Subjects: Cichlidae -- extra chromosomes -- large-sized B chromosomes; Biodiversity -- Latin America -- Periodicals; Ecology -- Latin America -- Periodicals; Natural history -- Latin America -- Periodicals; Latin America -- Environmental conditions -- Periodicals; 577.0980913
• DOI: 10.1080/23766808.2018.1429164
• Languages: English
• ISSNs: 2376-6808

Abstract

Abstract: Extra chromosomes are found in all major taxa, and their characteristics, function, and evolution are not yet completely understood. Known as B chromosomes, they are additional and dispensable genetic material that are present in particular individuals of certain populations of some species. In this work, we present the occurrence of B chromosomes in the cichlid Crenicichla lepidota from southern Brazil. The analyzed population showed 2 n = 48 chromosomes, plus 0, 2, 3, or 4 B chromosomes, being variable among metaphases (intraindividual variation). Morphologically, these B chromosomes were variable in size, similarly to the A chromosomes. B chromosomes did not show heterochromatization. Other cytogenetic markers, such as Nucleolar Organizing Region, CMA3/DAPI base-specific dyes, and Fluorescent in situ hybridization with 18S rDNA probe, showed no differences in relation to previous studies with C. lepidota . Although this is the second description of B chromosomes for this species, we highlight the specific features of this population, especially the similarity to A chromosomes, in relation to size, morphology, and heterochromatin accumulation. In summary the B chromosomes described herein are large to small-sized, euchromatic chromosomes, a result that contrasts with that obtained so far for Neotropical cichlids.