The mechanism of organelle relocation in human erythroblasts.

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K08315
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54010:Hematology and medical oncology-related
• Research Institution: Akita University
• Principal Investigator: Ubukawa Kumi (鵜生川久美) 秋田大学, 医学系研究科, 講師 (70646554)
• Co-Investigator(Kenkyū-buntansha): 高橋 直人 秋田大学, 医学系研究科, 教授 (80344753)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: ヒト赤芽球 / 脱核 / Cdc42

Outline of Final Research Achievements

The molecular mechanisms involved in the terminal differentiation of erythroblasts have been elucidated by comparing enucleation and cell division.
We herein investigated the effects of the cell division control protein 42 homolog (Cdc42) inhibitor, CASIN, on cytokinesis and enucleation in colony-forming units-erythroid (CFU-Es) and mature erythroblasts (day 10). CASIN blocked the proliferation of CFU-Es and their enucleation in a dose-dependent manner. Dynein adopted an island-like distribution in the cytoplasm of non-treated CFU-Es, but was concentrated near the nucleus as a dot and co-localized with γ-tubulin in CASIN-treated cells. CASIN blocked the accumulation of F-actin in CFU-Es and day 10 cells.
These results demonstrated that Cdc42 plays an important role in cytokinesis, nuclear polarization and nuclear extrusion through a relationship with dynein and actin filament organization during the terminal differentiation of erythroblasts.

Free Research Field

血液内科

Academic Significance and Societal Importance of the Research Achievements

ヒト赤芽球の分化、特に脱核時にCdc42が重要な役割を担うことを初めて示し、通常の細胞分裂と赤芽球脱核の類似点と相違点をまた一つ明らかにしたことに学術的意義がある。
社会的意義としては、赤血球の工業的産生への応用や疾患の病態解明があげられる。iPS細胞を用いた人工的赤血球産生においては、低い脱核率が問題となっており、赤芽球脱核のメカニズムを明らかにする本研究は、この問題点を解決する一助となる可能性がある。また、Cdc42阻害を含む細胞質分裂阻害剤が引き起こす赤芽球形態の異常は骨髄異形成症候群の赤芽球形態と類似点があり、病態解明に結び付く可能性がある。