More sex chromosomes than autosomes in the Amazonian frog Leptodactylus pentadactylus

Autor(es)

Gazoni, T. ^[1] ; Haddad, C. F. B. ^{[2, 3]} ; Narimatsu, H. ^[1] ; Cabral-de-Mello, D. C. ^[1] ; Lyra, M. L. ^{[2, 3]} ; Parise-Maltempi, P. P. ^[1]

Afiliação do(s) autor(es)

^[1] UNESP Univ Estadual Paulista, Inst Biociencias, Dept Biol, Campus Rio Claro, Sao Paulo - Brazil

^[2] UNESP Univ Estadual Paulista, Inst Biociencias, Dept Zool, Campus Rio Claro, Sao Paulo - Brazil

^[3] UNESP Univ Estadual Paulista, Inst Biociencias, Ctr Aquicultura CAUNESP, Campus Rio Claro, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CHROMOSOMA; v. 127, n. 2, p. 269-278, JUN 2018.
• Citações Web of Science: 7

Resumo

Heteromorphic sex chromosomes are common in eukaryotes and largely ubiquitous in birds and mammals. The largest number of multiple sex chromosomes in vertebrates known today is found in the monotreme platypus (Ornithorhynchus anatinus, 2n = 52) which exhibits precisely 10 sex chromosomes. Interestingly, fish, amphibians, and reptiles have sex determination mechanisms that do or do not involve morphologically differentiated sex chromosomes. Relatively few amphibian species carry heteromorphic sex chromosomes, and when present, they are frequently represented by only one pair, either XX:XY or ZZ:ZW types. Here, in contrast, with several evidences, from classical and molecular cytogenetic analyses, we found 12 sex chromosomes in a Brazilian population of the smoky jungle frog, designated as Leptodactylus pentadactylus Laurenti, 1768 (Leptodactylinae), which has a karyotype with 2n = 22 chromosomes. Males exhibited an astonishing stable ring-shaped meiotic chain composed of six X and six Y chromosomes. The number of sex chromosomes is larger than the number of autosomes found, and these data represent the largest number of multiple sex chromosomes ever found among vertebrate species. Additionally, sequence and karyotype variation data suggest that this species may represent a complex of species, in which the chromosomal rearrangements may possibly have played an important role in the evolution process. (AU)

• Processo FAPESP: 13/50741-7 - Diversidade e conservação dos anfíbios brasileiros
• Beneficiário: Célio Fernando Baptista Haddad
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático