Genetic sex determination in an XX-XY chromosome system can be realized through a locus on the Y chromosome that makes the undifferentiated gonad develop into a testis. Although this mechanism is widespread, only in two cases so far have the corresponding master male sex-determining genes been identified. One is Sry, which initiates testes determination in most mammals. The other is dmrt1bY (syn. dmy), from the fish medaka, Oryzias latipes. The mammalian Y is roughly estimated to be over 200 million years old. The medaka Y may be considerably younger. A comparative analysis of the genus Oryzias revealed that one sister species of the medaka has dmrt1bY on a homologous Y chromosome, whereas in another closely related species only a non-sex-linked pseudogene is present. In all other species, dmrt1bY was not detected. The divergence time for the different species was determined with mitochondrial DNA sequences. The timing was confirmed by independent calculations based on dmrt1 sequences. We show that the medaka sex-determining gene originated approximately 10 million years ago. This makes dmrt1bY and the corresponding Y chromosome the youngest male sex-determining system, at least in vertebrates, known so far.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cub.2004.09.026 | DOI Listing |
Animals (Basel)
January 2025
Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan 430223, China.
As a fundamental taxonomic group within vertebrates, fish represent an invaluable resource for investigating the mechanisms underlying sex determination and differentiation owing to their extensive geographical distribution and rich biodiversity. Within this biological cohort, the processes of sex determination and differentiation are intricately governed by both genetic factors and the complex interplay of environmental cues. While variations in external environmental factors, particularly temperature, can exert a modulatory influence on sex differentiation in fish to a limited degree, genetic factors remain the primary determinants of sexual traits.
View Article and Find Full Text PDF<b>Background and Objective:</b> In jojoba plants, the sex is usually difficult to identify, especially before flowering and during the very early stages of development. This stage is expected to facilitate breeding programs and adopt an invention and approach to isolate the GPAT gene identified between males and females: The study aimed at early diagnosis of sex in jojoba by sequence characterized by GPAT gene of sex-determining by simplex PCR. To prove the existence of the GPAT gene in male jojoba plants which may be the sex determination and identification in all plant systems.
View Article and Find Full Text PDFArch Med Res
January 2025
Programa de Investigación de Cancer de Mama, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico; Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico. Electronic address:
Na⁺/H⁺ exchanger regulatory factor 2 (NHERF2) is a nucleocytoplasmic protein initially identified as a regulator of membrane-bound sodium-hydrogen exchanger 3 (NHE3). In the cytoplasm, NHERF2 regulates the activity of G protein-coupled receptors (GPCRs), including beta-2 adrenergic receptor (2β-AR), lysophosphatidic acid receptor 2, and parathyroid hormone type 1 receptor. In the nucleus, NHERF2 acts as a coregulator of transcription factors such as sex-determining region Y protein (SRY), involved in male sex determination, and estrogen receptor alpha (ERα).
View Article and Find Full Text PDFDNA Res
December 2024
The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China.
Sex determination systems are diverse in echinoderms, however, our understanding is still very limited in this research field, especially for Asteroidea species. The northern Pacific seastar, Asterias amurensis, has attracted widespread concern due to its population outbreaks and high-risk invasions. Using whole-genome re-sequencing data from 40 females and 40 males, we identified a candidate sex determination region in A.
View Article and Find Full Text PDFAlthough sex determination is a fundamental process in vertebrate development, it is very plastic. Diverse genes became major sex determinants in teleost fishes. Deciphering how individual sex-determining genes orchestrate sex determination can reveal new actors in sexual development.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!