Changes in developmental program in the acquisition of novel morphological patterns of the turtle shell

2014 Fiscal Year Final Research Report

• Project Area: Genetic bases for the evolution of complex adaptive traits
• Project/Area Number: 22128003
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: The Institute of Physical and Chemical Research
• Principal Investigator: KURATANI Shigeru 独立行政法人理化学研究所, 倉谷形態進化研究室, 主任研究員 (00178089)
• Co-Investigator(Kenkyū-buntansha): IRIE Naoki 東京大学, 理学(系)研究科(研究院), 准教授 (10536121) ; PASCUAL-ANAYA-JUAN 国立研究開発法人理化学研究所, 倉谷形態進化研究室, 研究員 (30594098)
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 進化 / 発生 / ゲノム / バイオインフォマティクス / 脊椎動物 / カメ

Outline of Final Research Achievements

Turtles are characterized by the possession of the shell, whose dorsal moiety (carapace) is made by the modification of ribs and vertebral column. To understand the evolutionary process and developmental changes behind the acquisition of the carapace, we picked up Chinese soft-shelled turtle, Pelodiscus sinensis, and comparative embryological and genomic analyses were made. In the genome of P. sinensis, we identified Wnt5a as a candidate for the factor that exerts carapacial ridge formation and folding of body the wall specific to turtles. This project has also ascertained that the turtle is relatded to avians and crocodilians, as a group of archosaurians. It was also implied that the loss of sternum and distal ribs would have taken place in the turtle ancestor. Co-option of Wnt5a and further folding of the body wall would have taken place as the second step towards the turtles, and molecular developmental understanding of this mechanism will be the next project.

Free Research Field

生物学