The hnRNP Q-like gene is retroinserted into the B chromosomes of the cichlid fish Astatotilapia latifasciata

Autor(es)

Carmello, Bianca O. ^[1] ; Coan, Rafael L. B. ^[1] ; Cardoso, Adauto L. ^[1] ; Ramos, Erica ^[1] ; Fantinatti, Bruno E. A. ^[1] ; Marques, Diego F. ^[1] ; Oliveira, Rogerio A. ^[2] ; Valente, Guilherme T. ^[3] ; Martins, Cesar ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Inst Biosci, Dept Morphol, BR-18618689 Botucatu, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Inst Biosci, Dept Biostat, BR-18618689 Botucatu, SP - Brazil

^[3] Sao Paulo State Univ UNESP, Inst Biosci, Agron Sci Sch, Dept Bioproc & Biotechnol, BR-18610307 Botucatu, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Chromosome Research; v. 25, n. 3-4, p. 277-290, OCT 2017.
• Citações Web of Science: 4

Resumo

B chromosomes are dispensable elements observed in many eukaryotic species, including the African cichlid Astatotilapia latifasciata, which might have one or two B chromosomes. Although there have been many studies focused on the biology of these chromosomes, questions about the evolution, maintenance, and potential effects of these chromosomes remain. Here, we identified a variant form of the hnRNP Q-like gene inserted into the B chromosome of A. latifasciata that is characterized by a high copy number and intron-less structure. The absence of introns and presence of transposable elements with a reverse transcriptase domain flanking hnRNP Q-like sequences suggest that this gene was retroinserted into the B chromosome. RNA-Seq analysis did not show that the B variant retroinserted copies are transcriptionally active. However, RT-qPCR results showed variations in the canonical hnRNP Q-like copy expression levels among exons, tissues, sex, and B presence/absence. Although the patterns of transcription are not well understood, the exons of the B retrocopies were overexpressed, and a bias for female B+ expression was also observed. These results suggest that retroinsertion is an additional and important mechanism contributing to B chromosome formation. Furthermore, these findings indicate a bias towards female differential expression of B chromosome sequences, suggesting that B chromosomes and sex determination are somehow associated in cichlids. (AU)

• Processo FAPESP: 11/03807-7 - Integrando citogenética e genômica na compreensão da estrutura e evolução de cromossomos B em eucariotos utilizando o peixe ciclídeo Haplochromis obliquidens como modelo
• Beneficiário: César Martins
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/16661-1 - Cromossomos sexuais, cromossomos B e seus enigmas: sistemas modelo para estudos de evolução cromossômica e genômica
• Beneficiário: César Martins
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/04533-3 - Análise funcional de cromossomos B, utilizando o peixe ciclídeo Astatotilapia latifasciata como modelo
• Beneficiário: César Martins
• Modalidade de apoio: Auxílio à Pesquisa - Regular