Ayako Nakamura-Ishizu
   Department   School of Medicine, School of Medicine
   Position   Professor and Division head
Article types Original article
Language English
Peer review Peer reviewed
Title TUBB1 dysfunction in inherited thrombocytopenia causes genome instability.
Journal Formal name:British journal of haematology
Abbreviation:Br J Haematol
ISSN code:13652141/00071048
Domestic / ForeginForegin
Volume, Issue, Page 185(5),pp.888-902
Author and coauthor Matsumura Takayoshi, Nakamura-Ishizu Ayako, Takaoka Kensuke, Maki Hiroaki, Muddineni Siva S N A, Wang Chelsia Q, Suzushima Hitoshi, Kawakita Makoto, Asou Norio, Matsuoka Masao, Kurokawa Mineo, Osato Motomi, Suda Toshio
Publication date 2019/06
Summary Inherited thrombocytopenia is a genetically heterogeneous disease characterized by varying degrees of thrombocytopenia and risk of haematological malignancy, and the genetic cause of many cases remains unknown. We performed whole-exome sequencing of a family with thrombocytopenia and myeloid malignancy and identified a novel TUBB1 variant, T149P. Screening of other thrombocytopenia pedigrees identified another TUBB1 variant, R251H. TUBB1 encodes the tubulin β-1 chain, a major component of microtubules abundant in megakaryocytes. Variant TUBB1 disrupted the normal assembly of microtubules and impaired proplatelet formation in vitro. In addition, DNA damage response was severely attenuated by loss of TUBB1. We found that the nuclear accumulation of p53 (also termed TP53) and the expression of pro-apoptotic genes triggered by genotoxic stress were blocked in TUBB1-deficient cells and, accordingly, apoptosis after DNA damage was diminished by knockdown of TUBB1. Thus, we have demonstrated that microtubule dysfunction confers resistance to apoptosis, even in DNA damage-accumulated cells, which explains genome instability in the affected individuals. These studies will lead us to a better understanding of how microtubule dysfunction can contribute to the accumulation of DNA damage, genetic instability and leukaemogenesis.
DOI 10.1111/bjh.15835
PMID 30854628