Gender in plants: sex chromosomes are emerging from the fog

• Published in: Trends in genetics Vol. 20; no. 9; pp. 432 - 438
• Main Authors: Vyskot, Boris, Hobza, Roman
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-09-2004; Elsevier Science
• Subjects: Biological and medical sciences; Carica papaya; Chromosome Mapping; cytogenetics; dioecy; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; literature reviews; Metaphase; Molecular and cellular biology; papayas; plant genetics; plants; Plants - genetics; sex chromosomes; sex determination; X chromosome; X Chromosome - genetics; Y chromosome; Y Chromosome - genetics; Genetics; Plant; Vegetals; Sex chromosome; Sex
• ISSN: 0168-9525
• DOI: 10.1016/j.tig.2004.06.006

Although most plants have flowers with both male and female sex organs, there are several thousands of plant species where male or female flowers form on different individuals. Surprisingly, the presence of well-established sex chromosomes in these dioecious plants is rare. The best-described example is white campion, for which large sex chromosomes have been identified and mapped partially. A recent study presented a comprehensive genetic and physical mapping of the genome of dioecious papaya. It revealed a short male specific region on the Y chromosome (MSY) that does not recombine with the X chromosome, providing strong evidence that the sex chromosomes originated from a regular pair of autosomes. The primitive papaya Y chromosome thus represents an early event in sex chromosome evolution. In this article, we review the current status of plant sex-chromosome research and discuss the advantages of different dioecious models.