Publication Date:
2009-12-08
Description:
Although the nematode Caenorhabditis elegans produces self-fertile hermaphrodites, it descended from a male/female species, so hermaphroditism provides a model for the origin of novel traits. In the related species C. remanei, which has only male and female sexes, lowering the activity of tra-2 by RNA interference created XX animals that made spermatids as well as oocytes, but their spermatids could not activate without the addition of male seminal fluid. However, by lowering the expression of both tra-2 and swm-1, a gene that regulates sperm activation in C. elegans, we produced XX animals with active sperm that were self-fertile. Thus, the evolution of hermaphroditism in Caenorhabditis probably required two steps: a mutation in the sex-determination pathway that caused XX spermatogenesis and a mutation that allowed these spermatids to self-activate.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Baldi, Chris -- Cho, Soochin -- Ellis, Ronald E -- New York, N.Y. -- Science. 2009 Nov 13;326(5955):1002-5. doi: 10.1126/science.1176013.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Graduate School of Biomedical Sciences, University of Medicine and Dentistry of New Jersey, Stratford, NJ 08084, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19965511" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Sequence
;
Animals
;
Base Sequence
;
*Biological Evolution
;
Caenorhabditis/anatomy & histology/classification/*genetics/*physiology
;
Caenorhabditis elegans/anatomy & histology/classification/*genetics/*physiology
;
Caenorhabditis elegans Proteins/genetics/physiology
;
Crosses, Genetic
;
Disorders of Sex Development/genetics
;
Female
;
Genes, Helminth
;
Germ Cells/physiology
;
Male
;
Membrane Proteins/genetics/physiology
;
Molecular Sequence Data
;
*Mutation
;
Oogenesis
;
Ovulation
;
Phylogeny
;
Reproduction
;
Selection, Genetic
;
Sex Determination Processes
;
Spermatids/physiology
;
Spermatogenesis
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
