Fofou Yonta Tostani

Biochemistry, biophysics, and functional analysis of molecular motor proteins

Elucidation of the mechanistic control of kinesin molecular motors.

Our research aims to elucidate the functional regulatory mechanisms of kinesin motor proteins, which play a central role in mitosis. In particular, we have focused on the loop 5 (L5) structure, which is targeted by kinesin Eg5-specific inhibitors, and have revealed that this structure is a crucial factor in determining inhibition sensitivity. Furthermore, in the model organism Caenorhabditis elegans, we performed functional analyses using biochemical and biophysical methods on BMK-1, a homolog of Eg5, and KLP-18, which is involved in mitosis, demonstrating that the L5-dependent inhibition mechanism is conserved. These studies suggest that kinesin function and inhibition sensitivity can be regulated through the control of the loop 5 structure, providing a foundation for in vivo control of molecular motors. Moving forward, we aim to develop precise control technologies for kinesin function using photoresponsive molecules, with applications in cell division control and the development of novel anticancer drugs.
Research focuses on elucidating the regulatory mechanisms of kinesin motor proteins that play central roles in mitosis. Kinesins are ATP-driven molecular motors that move along microtubules and are essential for proper spindle formation during cell division.Particular attention is given to the mitotic kinesin Eg5 and the structural role of loop 5 (L5) as a determinant of inhibitor sensitivity. Using the model organism Caenorhabditis elegans, biochemical and biophysical analyzes are conducted on homologous kinesins, including BMK-1 and KLP-18, demonstrating conserved L5-dependent inhibition mechanisms. These findings suggest that modulation of loop 5 structure enables regulation of kinesin function and inhibitor sensitivity, providing a foundation for the in vivo control of molecular motors. Future work aims to develop precise regulation strategies using photoresponsive molecules, with potential applications in cell division control and anticancer therapeutics.

Biochemistry, molecular biology, microbiology

September 2014
Admission to the Department of Biochemistry, University of Cameroon

March 2018
Graduated from the same university

April 2019
Soka University Language and Culture Education Center (Non-Degree) Admission

March 2020
Completed at the same center.

April 2020
Soka University Graduate School, Graduate School of Science and Engineering Biosciences Major, Master Course , Enrollment

March 2022
Completed Master's program in the same department and major at the same graduate school.

April 2023
Soka University Graduate School, Graduate School of Science and Engineering Biosciences Major, Doctoral Course , Enrollment

March 2026 (planned)
Completed doctoral program in the same department and graduate school.

April 2026
Soka University Faculty of Science and Engineering Assistant Professor

April 2020
Joined Soka University Graduate School as a Teaching Assistant (TA).

March 2022
Term of office has expired.

April 2022
Joined Big Motor Co., Ltd. (now WE CARS)

December 2022
Retirement from the company

January 2023
Joined Tech Mahindra Japan Co., Ltd.

March 2026 (planned)
Retirement from the company

April 2023
Hired as a Research Assistant (RA) at Soka University.

March 2026 (planned)
Term of office has expired.

Japanese Biochemical Society
Biophysical Society of Japan
Biophysical Society

Tostani, F.Y., Kurosaka, T., Nishibe, N., Maruta, S.
Loop L5 determines sensitivity of Caenorhabditis elegans kinesin BMK-1 to the kinesin Eg5-specific inhibitor.
Biosci. Biotechnol. Biochem. 90(3), 352–360 (2026).
DOI: https://doi.org/10.1093/bbb/zbaf188