A rare case of intra-ovarian oocyte maturation.
Zygote
; 32(3): 256-260, 2024 Jun.
Article
em En
| MEDLINE
| ID: mdl-38828553
ABSTRACT
The intra-ovarian presence of ootids, i.e. female gametes that have completed meiosis, is considered exceptional in the animal kingdom. The present study explores the first such case to be reported in a sea cucumber (Echinodermata Holothuroidea). In the overwhelming majority of animals, including holothuroids, oocytes (i.e. immature female gametes) that are developing in the ovary undergo a primary arrest at the prophase stage of meiosis, which may last from days to decades. In free-spawning taxa, this arrest is normally lifted only during or shortly before transit in the gonoduct, when gamete release (spawning) is imminent. However, oocytes of the holothuroid Chiridota laevis were discovered to have resumed the second meiotic division including the completion of germinal vesicle breakdown and polar-body expulsion inside the ovary, effectively reaching the ootid stage concomitantly with ovulation (i.e. escape from follicle cells) prior to spawning. The potential drivers and significance of this exceptionally rare case of full intra-ovarian oogenic maturation are discussed.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oócitos
/
Oogênese
/
Ovário
/
Meiose
Limite:
Animals
Idioma:
En
Revista:
Zygote
Assunto da revista:
EMBRIOLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Canadá