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Published on: August 22, 2013
Sex determination in papaya.
Ray Ming1, Qingyi Yu, Paul H Moore
1Department of Plant Biology, University of Illinois at Urbana-Champaign, 288 ERML, MC-051, 1201 W. Gregory Drive, Urbana, IL 61801, USA. rming@life.uiuc.edu
Seminars in Cell & Developmental Biology
|March 14, 2007
Summary
Papaya sex determination is controlled by primitive sex chromosomes and a male-specific region (MSY). Two genes, one feminizing and one masculinizing, regulate this complex process, with implications for papaya production.
Area of Science:
- Plant genetics
- Molecular biology
- Reproductive biology
Background:
- Sex determination in papaya is complex, with multiple hypotheses proposed over decades.
- Previous theories included single genes, linked genes, genic balance, XY chromosomes, and regulatory elements.
Purpose of the Study:
- To elucidate the genetic and molecular mechanisms underlying sex determination in papaya.
- To characterize the genomic region responsible for sex determination.
Main Methods:
- High-density linkage mapping to identify recombination suppression.
- Physical mapping and sequencing of the non-recombination region.
- Postulating gene functions based on developmental observations.
Main Results:
- Recombination suppression at the sex determination locus was validated.
- Papaya sex determination is controlled by primitive sex chromosomes with a male-specific region (MSY).
- Two genes are proposed: a feminizing gene (stamen suppressor) and a masculinizing gene (carpel suppressor).
Conclusions:
- Sex determination in papaya involves a pair of primitive sex chromosomes and a small MSY.
- Two key genes likely regulate stamen and carpel development, influencing overall sex determination.
- Understanding these genes can significantly benefit papaya production.
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