Functional analysis of B chromosome presence using cichlid Astatotilapia latifasciata as model

Author(s)

Diego Ferreira Marques

• Document type: Doctoral Thesis
• Press: Botucatu. 2016-07-29.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências. Botucatu
• Defense date: 2016-07-18
• Advisor: Cesar Martins

Abstract

Supernumerary chromosomes (B chromosomes) are extra elements, not homologous to the A complement and have been described in a range of species in eukaryotes. Studies with these elements have been focused in structural level, and functional aspects have been poorly explored. Among fish species, cichlids have gaining scientific interest because the rapid and extensive adaptive radiation process occurred in the group and B chromosomes have been described in 21 cichlid species, ranging in number from one to three. Considering these aspects, linked to the possibility of using tools that integrate functional and genomic data and cytogenetics, we aimed to analyze transcriptional profiles of target tissues of A. latifasciata in order to investigate possible interference motivated by B chromosome related to the transcript expression levels in individuals with the presence or absence of this extra element. A range of genes differentially expressed evidenced in the analyzed tissues shows that B chromosome may be interfering in different pathways. The results contributed to the discussion of functional aspects of B chromosome, identifying several genes related to cell cycle, maintenance of cell structure and immune response. Highly expressed genes located on B were identified. However, the majority of highly expressed genes is located on chromosomes of the normal complement and seems to be affected by the presence of B. Furthermore, our data suggest a possible repressive action of B chromosome in tests and increasing expression genes in ovarian confirming the action of drive mechanism of this chromosome in female gametic cells. (AU)

• FAPESP's process: 12/16288-0 - FUNCTIONAL ANALYSIS OF THE PRESENCE OF B CHROMOSOME USING Astatotilapia latifasciata (CICHLID FISH) AS A MODEL
• Grantee: Diego Ferreira Marques
• Support Opportunities: Scholarships in Brazil - Doctorate