Identification of sex determination genes in papaya by comapring sex chromsome sequences

2015 Fiscal Year Final Research Report

• Project/Area Number: 25450004
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Science in genetics and breeding
• Research Institution: Shinshu University
• Principal Investigator: MATSUMURA Hideo 信州大学, 学術研究院繊維学系, 准教授 (40390885)
• Co-Investigator(Renkei-kenkyūsha): URASAKI Naoya 沖縄県農業研究センター, 研究企画班, 上席主任研究員 (20504591) ; TARORA Kazuhiko 沖縄県農業研究センター, 研究企画班, 主任研究員 (10504772)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 性決定 / 性染色体 / ゲノム解析 / MADS-box / パパイヤ

Outline of Final Research Achievements

Papaya (Carica papaya) is a trioecious plant species, and its sex types were determined by sex chromosomes (X, Y, Yh). In the present study, genome sequences of Y and Yh chromosomes were analyzed and their structural differences were identified. Consequently, only a SVP-like gene, harbouring MADS-box domain, showed apparent structural difference between Y and Yh chromosomes. In its allele on the Yh chromosome, a transposon was inserted and 5' region was truncated in its transcript, resulting in loss of MADS-box domain in its encoded protein. RT-PCR analysis and transient expression study in Nicotiana benthamiana leaves demonstrated that expression product from its allele in Yh chromosome was possibly unstable. Therefore, this SVP-like gene was supposed to be a candidate gene for male/hermaphrodite determination in papaya. Additionally, RNA-seq analysis of X chromosomal genes showed possibility of gene dosage compensation between female and hermaphrodite.

Free Research Field

植物育種学