Evolution of “determinants” in sex determination: A novel hypothesis for the origin of environmental contingencies in avian sex bias
(2009) In Seminars in Cell & Developmental Biology 20(3). p.304-312- Abstract
- Abstract in Finnish
Sex-determination is commonly categorized as either "genetic" or "environmental"-a classification that obscures the origin of this dichotomy and the evolution of sex-determining factors. The current focus on static outcomes of sex-determination provides little insight into the dynamic developmental processes by which some mechanisms acquire the role of sex determinants. Systems that combine "genetic" pathways of sex-determination (i.e., sex chromosomes) with "environmental" pathways (e. g., epigenetically induced segregation distortion) provide an opportunity to examine the evolutionary relationships between the two classes of processes and, ultimately, illuminate the evolution of sex-determining systems. Taxa with... (More) - Abstract in Finnish
Sex-determination is commonly categorized as either "genetic" or "environmental"-a classification that obscures the origin of this dichotomy and the evolution of sex-determining factors. The current focus on static outcomes of sex-determination provides little insight into the dynamic developmental processes by which some mechanisms acquire the role of sex determinants. Systems that combine "genetic" pathways of sex-determination (i.e., sex chromosomes) with "environmental" pathways (e. g., epigenetically induced segregation distortion) provide an opportunity to examine the evolutionary relationships between the two classes of processes and, ultimately, illuminate the evolution of sex-determining systems. Taxa with sex chromosomes typically undergo an evolutionary reduction in size of one of the sex chromosomes due to suppressed recombination, resulting in pronounced dimorphism of the sex chromosomes, and setting the stage for emergence of epigenetic compensatory mechanisms regulating meiotic segregation of heteromorphic sex chromosomes. Here we propose that these dispersed and redundant regulatory mechanisms enable environmental contingency in genetic sex-determination in birds and account for frequently documented context-dependence in avian sex-determination. We examine the evolution of directionality in such sex-determination as a result of exposure of epigenetic regulators of meiosis to natural selection and identify a central role of hormones in integrating female reproductive homeostasis, resource allocation to oocytes, and offspring sex. This approach clarifies the evolutionary relationship between sex-specific molecular genetic mechanisms of sex-determination and non-sex-specific epigenetic regulators of meiosis and demonstrates that both can determine sex. Our perspective show show non-sex-specific mechanisms can acquire sex-determining function and, by establishing the explicit link between physiological integration of oogenesis and sex-determination, opens new avenues to the studies of adaptive sex-bias and sex-specific resource allocation in species with genetic sex-determination (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4739114
- author
- Uller, Tobias LU and Badyaev, Alexander
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Seminars in Cell & Developmental Biology
- volume
- 20
- issue
- 3
- pages
- 304 - 312
- publisher
- Academic Press
- external identifiers
-
- scopus:63849083596
- pmid:19073270
- ISSN
- 1084-9521
- DOI
- 10.1016/j.semcdb.2008.11.013
- language
- English
- LU publication?
- no
- id
- 97c46a9d-63be-43e1-a851-8e6a0853d667 (old id 4739114)
- date added to LUP
- 2016-04-01 14:16:54
- date last changed
- 2022-02-04 20:03:35
@article{97c46a9d-63be-43e1-a851-8e6a0853d667,
abstract = {{Abstract in Finnish<br/>Sex-determination is commonly categorized as either "genetic" or "environmental"-a classification that obscures the origin of this dichotomy and the evolution of sex-determining factors. The current focus on static outcomes of sex-determination provides little insight into the dynamic developmental processes by which some mechanisms acquire the role of sex determinants. Systems that combine "genetic" pathways of sex-determination (i.e., sex chromosomes) with "environmental" pathways (e. g., epigenetically induced segregation distortion) provide an opportunity to examine the evolutionary relationships between the two classes of processes and, ultimately, illuminate the evolution of sex-determining systems. Taxa with sex chromosomes typically undergo an evolutionary reduction in size of one of the sex chromosomes due to suppressed recombination, resulting in pronounced dimorphism of the sex chromosomes, and setting the stage for emergence of epigenetic compensatory mechanisms regulating meiotic segregation of heteromorphic sex chromosomes. Here we propose that these dispersed and redundant regulatory mechanisms enable environmental contingency in genetic sex-determination in birds and account for frequently documented context-dependence in avian sex-determination. We examine the evolution of directionality in such sex-determination as a result of exposure of epigenetic regulators of meiosis to natural selection and identify a central role of hormones in integrating female reproductive homeostasis, resource allocation to oocytes, and offspring sex. This approach clarifies the evolutionary relationship between sex-specific molecular genetic mechanisms of sex-determination and non-sex-specific epigenetic regulators of meiosis and demonstrates that both can determine sex. Our perspective show show non-sex-specific mechanisms can acquire sex-determining function and, by establishing the explicit link between physiological integration of oogenesis and sex-determination, opens new avenues to the studies of adaptive sex-bias and sex-specific resource allocation in species with genetic sex-determination}},
author = {{Uller, Tobias and Badyaev, Alexander}},
issn = {{1084-9521}},
language = {{eng}},
number = {{3}},
pages = {{304--312}},
publisher = {{Academic Press}},
series = {{Seminars in Cell & Developmental Biology}},
title = {{Evolution of “determinants” in sex determination: A novel hypothesis for the origin of environmental contingencies in avian sex bias}},
url = {{http://dx.doi.org/10.1016/j.semcdb.2008.11.013}},
doi = {{10.1016/j.semcdb.2008.11.013}},
volume = {{20}},
year = {{2009}},
}