Researcher Information

NAKATOMI Akiko

Associate Professor

Developing human resources who will open up a new era

Office for Education and Research Strategy

basic_photo_1
Theme

Survey and research of new education system in School of Science and related graduate schools

FieldFunctional biochemistry, Protein chemistry, Intracellular signal transduction
KeywordProtein phosphorylation and dephosphorylation, Calcium signaling, Phosphatase, Calcineurin, Calmodulin

Introduction of Research

Calcineurin (also known as protein phosphatase 3) is one of the serine/threonine phosphatase that is controlled directly by Ca2+ and calmodulin. The functions of calcineurin have been studied most extensively in T lymphocytes, where calcineurin transduces immunogenic signals in response to T cell receptor activation, but we are interested in the function of calcineurin in testis. It has been thought that calcineurin is related to spermiogenesis, and later, to the regulation of flagellar motility, because expression of calcineurin fluctuates during the cycle of spermatogenesis, peaking after meiosis. However, any definite physiological functions of calcineurin in testis are not elucidated.
In recent years, a growing numbers of calcineurin-binding proteins have been discovered from various tissues, most of which can inhibit the phosphatase activity of calcineurin. These proteins seem to function as tissue specific regulator for calcineurin. We found a gonad specific calcineurin-binding protein, CaNBP75. This protein also bound a small G protein, Ran. CaNBP75 may function as a mediator for crosstalk between signaling pathways of Ca2+ regulation and the small G protein mediated regulation in spermatogenesis, and functional analyses of CaNBP75 help to understand the physiological function of calcineurin in testis.

Representative Achievements

Reconstituted human myosin light chain phosphatase reveals distinct roles of two inhibitory phosphorylation sites of the regulatory subunit, MYPT1.
Khasnis M, Nakatomi A, Gumpper K, Eto M.
Biochemistry 53(16) 2701-2709 Apr 2014
Ran and calcineurin can participate collaboratively in the regulation of spermatogenesis in scallop.
Hino H, Arimoto K, Yazawa M, Murakami Y, Nakatomi A
Marine biotechnology (New York, N.Y.) 14(4) 479-490 Aug 2012
Specific conformation and Ca(2+)-binding mode of yeast calmodulin: insight into evolutionary development.
Nakashima K, Ishida H, Nakatomi A, Yazawa M
Journal of biochemistry 152(1) 27-35 Jul 2012
Roles of the C-terminal residues of calmodulin in structure and function
Kitagawa, Chihiro; Nakatomi, Akiko; Hwang, Dasol; Osaka, Issey; Fujimori, Hiroki; Kawasaki, Hideya; Arakawa, Ryuichi; Murakami, Yota; Ohki, Shinya
BIOPHYSICS 7 35-49 2011
Identification and characterization of a novel calcineurin-binding protein in scallop testis.
Nakatomi A, Yazawa M
Journal of biochemistry 133(2) 159-164 Feb 2003
Academic degreePh.D.
Self Introduction

I’m working on the Ambitious Leader’s program, as a bridge between graduate students and the program. Please feel free to ask me about participating in the program or proceeding to the doctor course.

Academic background1996 B. S., Department of Chemistry II, School of Science, Hokkaido University
1998 M. S., Department of Chemistry, Graduate School of Science, Hokkaido University
2003 Ph.D., Department of Chemistry, Graduate School of Science, Hokkaido University
2003 Instructor, Faculty of Science, Hokkaido University
2006 Instructor, Faculty of Advanced Life Science, Hokkaido University
2007 Assistant Professor, Faculty of Advanced Life Science, Hokkaido University
2010 Assistant Professor, Faculty of Science, Hokkaido University
2014 Specially Appointed Associate Professor, Faculty of Science, Hokkaido University
2019- Present position
Affiliated academic societyThe Japanese Biochemical Society, Japanese Association for Protein Phosphatase Research
ProjectHokkaido University Ambitious Leader's Program
Room addressScience Building 5 5-213