Meiotic chromosomes in fish: synaptic behavior and transcriptional status visualized by immunofluorescence.

• Grant number: 17/15608-5
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2018
• End date: January 31, 2020
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: Fausto Foresti
• Grantee: Fausto Foresti
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated researchers: Claudio de Oliveira

Abstract

During the early stages of prophase I in meiosis, the cells undergo a significant decrease in their transcriptional activity, related to the synaptic states of the homologous chromosomes. This phenomenon is known as Meiotic Silencing of Unsynapsed Chromatin (MSUC), and describes the cascade of chromatin remodeling events, tending to limit gene expression during the onset of meiosis. The emergence of the heteromorphic sex chromosomes (ZW and XY), conflicts with the mechanisms of meiosis control, since these chromosomes, in most cases, only have a small homologous portion, leaving a great extension of non-synapted chromatin, being able to recognize in these organisms, a special type of MSUC, called Meiotic Sex Chromosomes Inactivation (MSCI), which appears as a complementary mechanism of the MSUC, guaranteeing the normal advancement of the cells by prophase I. Although the sexual pairs ZW and XY are the most studied, within vertebrates, fish appear as an excellent study model because it has alternative chromosomal sex determination systems, from hemizygous systems to multiple systems. The latter, are characteristic of an endemic order of fish from the Neotropical region, the Gymnotiformes, thus offering an alternative model for the study of the MSCI because they are sex chromosomes arising from centric fusion, where the processes of degeneration and differentiation of sex chromosomes XY and ZW would not be so obvious. In the present project we intend to use the specific prophase I markers to evaluate the synaptic behavior and the transcriptional status of the sex chromosomes of Eigenmannia sp2, Gymnotus pantanal and Brachyhypopomus pinnicaudatus, which share the multiple sex chromosome system X1X1X2X2 / X1X2Y, as a first step to understand the meiotic inactivation processes of sex chromosomes (MSCI) in fish. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ANDRES ARAYA-JAIME, CRISTIAN; ZERBINATO DE ANDRADE SILVA, DUILIO MAZZONI; RIBEIRO DA SILVA, LUIS RICARDO; NEVES DO NASCIMENTO, CRISTIANO; OLIVEIRA, CLAUDIO; FORESTI, FAUSTO. Karyotype description and comparative chromosomal mapping of rDNA and U2 snDNA sequences in Eigenmannia limbata and E. microstoma (Teleostei, Gymnotiformes, Sternopygidae). COMPARATIVE CYTOGENETICS, v. 16, n. 2, p. 16-pg., 2022-05-05. (17/15608-5, 17/22447-8, 14/09634-5, 16/09204-6, 14/26508-3, 18/20610-1)

DUÍLIO MAZZONI ZERBINATO DE ANDRADE SILVA; CRISTIAN ARAYA-JAIME; MASAKANE YAMASHITA; MATEUS ROSSETTO VIDAL; CLAUDIO OLIVEIRA; FÁBIO PORTO-FORESTI; ROBERTO FERREIRA ARTONI; FAUSTO FORESTI. Meiotic self-pairing of the Psalidodon (Characiformes, Characidae) iso-B chromosome: A successful perpetuation mechanism. GENETICS AND MOLECULAR BIOLOGY, v. 44, n. 3, 2021-10-04. (14/09634-5, 14/26508-3, 17/22447-8, 17/15608-5, 16/09204-6, 18/20610-1)