Receptor Programme Seminar

Adj. Prof. Maria Vartiainen, Institute of Biotechnology, University of Helsinki
Actin’ on Transcription

Host: Jukka Ali-Nikula (juilal@utu.fi)

Maria Vartiainen studied molecular biology at the University of Jyväskylä, and obtained her MSc in 1999. She did her PhD thesis with Pekka Lappalainen at the Institute of Biotechnology (BI), graduating in 2002.  After this Maria worked as a post-doc funded by the EMBO Long Term Fellowship in the lab of Richard Treisman at London Research Institute of Cancer Research UK 2003-2007. There she developed interest in nuclear functions of actin especially in regulating gene expression. Maria returned to BI in 2007 as a group leader, and is currently also the scientific leader of the Light Microscopy Unit (LMU) at BI. Her laboratory wants to understand the mechanisms by which actin operates in the nucleus to regulate essential nuclear events, such as gene expression and maintenance of genomic integrity. She is especially interested in the role of actin in transcription by RNA polymerase II, and her studies have shown that actin interacts with virtually all transcribed genes.

Selected publications
Viita T, Kyheröinen S, Prajapati B, Virtanen J, Varjosalo M, Vartiainen MK. Nuclear actin interactome analysis links actin to KAT14 histone acetyl transferase and mRNA splicing. J Cell Sci 2019

Sokolova M, Moore HM, Prajapati B, Dopie J, Merilainen L, Honkanen M, Matos RC, Poukkula M,  Hietakangas V, Vartiainen MK Nuclear actin is required for transcription during Drosophila oogenesis iScience 2018 Nov 30;9:63-70.

Nevzorov I, Sidorenko E, Wang W, Zhao H, Vartiainen MK. Myosin-1C uses a novel phosphoinositide-dependent pathway for nuclear localization. EMBO Rep. 2018 Feb;19(2):290-304.

Moore HM, Vartiainen MK. F-actin organizes the nucleus. Nat Cell Biol. 2017 Nov 29;19(12):1386-1388

Kristó I, Bajusz C, Borsos BN, Pankotai T, Dopie J, Jankovics F, Vartiainen MK, Erdélyi M, Vilmos P. The actin binding cytoskeletal protein Moesin is involved in nuclear mRNA export. Biochim Biophys Acta. 2017 Oct;1864(10):1589-1604.

Virtanen JA, Vartiainen MK. Diverse functions for different forms of nuclear actin. Curr Opin Cell Biol. 2017 Jun;46:33-38.

Rajakylä EK, Viita T, Kyheröinen S, Huet G, Treisman R, Vartiainen MK. RNA export factor Ddx19 is required for nuclear import of the SRF coactivator MKL1. Nat Commun. 2015 Jan 14;6:5978.

Huet G, Rajakylä EK, Viita T, Skarp KP, Crivaro M, Dopie J, Vartiainen MK. Actin-regulated feedback loop based on Phactr4, PP1 and cofilin maintains the actin monomer pool.  J Cell Sci. 2013 Jan 15;126(Pt 2):497-507.

Dopie J, Skarp KP, Rajakylä EK, Tanhuanpää K, Vartiainen MK. Active maintenance of nuclear actin by importin 9 supports transcription. Proc Natl Acad Sci U S A. 2012 Feb 28;109(9):E544-52