Professional and academic career
5-year Academy Research Fellow (Academy of Finland) (August 2008- February 2015), project leader in Neuroscience Center.
Post-doctoral training in Pekka Lappalainen´s group 01.08.2002-31.07.2008: Projects: 1) Identification of the roles of ADF and cofilin-1 in mammalian non-muscle cells, 2) Analysis of stress fiber assembly by light microscopy methods and 3) Analysis of the mechanism of actin-based plasticity in dendritic spines. University of Helsinki.
Ph.D. studies 1.11.98-31.06.2002 in Martin Bähler´s group: SWAP-70 identifies a transitional subset of actin filaments in motile cells. I first worked on my thesis project in Munich and then, due to move of the laboratory, my studies continued in Münster. During the thesis work I also spent two times two weeks in professor Victor Small´s laboratory in Salzburg (now his laboratory is in Vienna). LMU Munich and University of Münster (Germany).
Research working 01.06.98-31.09.98 in Carina Wallgren-Pettersson´s and Albert de la Chapelle´s group: Mutational analysis of the nebulin gene. University of Helsinki.
Master´s thesis work 01.11.97-31.05.98 in Carina Wallgren-Pettersson´s and Albert de la Chapelle´s group: Genetically heterogeneous recessive form nemaline myopathy. University of Helsinki.
Honours and awards
2014-2017: Four-year Academy of Finland project: Regulation of dendritic filopodia by intracellular pH and membrane curvature: 526 642 Eur.
2013-2015: CIMO funding 1 ½ year: 21 600 EUR.
2012-2014: Three-year Helsinki University research grant: Regulation of dendritic spine structural and functional plasticity by the actin cytoskeleton: 120 000 Eur.
2008-2015: Five-year Academy Research Fellow of the Academy of Finland: Regulation of the actin cytoskeleton in dendritic spines: own salary + 406 502 Eur.
2009- Neuroscience Center grant: ½-1 PhD student salary.
2005-2008: Three-year post-doctoral fellow of the Academy of Finland: Formation, morphology and dynamics of stress fibers: 168 090 Eur.
General administrative and organisational experience
Member of the Programme Committee:
2016 FENS Forum in Copenhagen,
2014 Neuroscience Viikki Day, Helsinki (100 participants).
2013 Neuroscience Finland, Helsinki, topics: Optogenetics and deep brain stimulation (200 participants)
2010 Actin research on your campus symposium, Helsinki (50 participants)
Positions of trust, merits and activities in society, institutional responsibilities:
Board member in Brain research Society of Finland (2008-present), field molecular neurobiology
Vice coordinator in Viikki Research Groups in Biosciences organization (2013-present)
Vice board member of the Neuroscience Center board (2014-present)
Vice board member of the MNEURO program (2014-present)
Member of Novartis award committee 2009 –best PhD thesis in Neuroscience in Finland 2008.
Most excitatory synapses in the mammalian brain are formed at dendritic spines. Changes in spine morphology account for functional differences at the synaptic level. The actin cytoskeleton plays a pivotal role in the formation and elimination, motility and stability, and size and shape of dendritic spines as well as in changes occurring during synaptic plasticity. Various memory disorders involve defects in the regulation of the actin cytoskeleton.
The main goal of my group is to elucidate the mechanisms of actin cytoskeleton regulation in dendritic spines and to reveal how regulation of cytoskeletal dynamics affects dendritic spine development, morphology and plasticity. We are taking a bottom-up approach, where molecular mechanisms learnt in simpler in vitro systems, such as test tubes, fibroblasts or dissociated hippocampal neurons, are taken to more complex systems, such as acute brain slices and the in vivo brain. In all levels, advanced microscopy techniques play a major role.
- Koskinen, M. and Hotulainen, P. (2014)Measuring F-actin properties in dendritic spines. Front. Neuroanat. 8, 74.
- Koskinen, M., Bertling E., Hotulainen, R., Tanhuanpää, K. and Hotulainen, P. Myosin IIb controls actin dynamics underlying the dendritic spine maturation. Mol. Cell. Neurosci. 61C, 56-64. Cited 1.
- Koskinen, M., Bertling E., and Hotulainen, P. (2012) Methods to measure actin treadmilling rate in dendritic spines. Methods in Enzymology 505, 47-58. Cited 7.
- Bertling E., Ludwig, A., Koskinen, M., and Hotulainen, P. (2012) Methods for three-dimensional analysis of dendritic spine dynamics. Methods in Enzymology 506, 391-406. Cited 2.
- Tojkander, S., Gateva, G., Schevzov, G., Hotulainen, P.,Naumanen, P., Martin, C., Gunning, P.W., and Lappalainen, P. (2011) A molecular pathway for myosin II recruitment to stress fibers. Curr. Biol. 21, 539-550. Cited 54.
- Hotulainen, P., and Hoogenraad, C.C. (2010) Actin in dendritic spines: connecting dynamics to function. J. Cell Biol. 189, 619-629. Cited 194.
- Hotulainen, P., Llano, O., Smirnov, S., Tanhuanpää, K., Faix, J., Rivera, C., Lappalainen, P. (2009) Defining mechanisms of actin polymerization and depolymerization during dendritic spine morphogenesis. J. Cell Biology 185, 323-339. Cited 108.
- Skwarek-Maruszewska, A., Hotulainen, P., Mattila, P.K., and Lappalainen, P. (2009) Contractility-dependent actin dynamics in cardiomyocyte sarcomeres. J. Cell Science 122, 2119-2126. Cited 37.
- Naumanen, P., Lappalainen, P., Hotulainen, P. (2008): Mechanisms of actin stress fibre assembly. J. Microscopy 231, 446-454. Cited 78.
- Hotulainen, P., and Lappalainen, P. (2006) Stress-fibers are generated by two distinct actin assembly mechanisms in motile cells. J. Cell Biol. 173, 383-394. Cited 328.
- Hotulainen, P., Paunola, E., Vartiainen, M.K., and Lappalainen, P. (2005) ADF and cofilin-1 play overlapping roles in promoting rapid F-actin depolymerization in mammalian non-muscle cells. Mol. Biol. Cell.16, 649-664. Cited 188.
- Bertling, E., Hotulainen, P., Mattila, P.K., Matilainen, T., Salminen, M., and Lappalainen, P. (2004) Cyclase-associated protein 1 (CAP1) promotes cofilin-induced actin dynamics in mammalian nonmuscle cells. Mol. Biol. Cell 15, 2324-34. Cited 83.
- Hilpelä, P., Vartiainen, M.K., and Lappalainen, P. (2003) Regulation of the actin cytoskeleton by PI(4,5)P2 and PI(3,4,5)P3. Curr. Topics Microbiol. Immunol. 282, 117-163. Cited 54.
- Hilpelä, P.,Oberbanscheidt, P., Hahne, P., Hund, M., Kalhammer, G., Small, J.V., and Bähler, M. (2003) SWAP-70 identifies a transitional subset of actin filaments in motile cells. Mol. Biol. Cell 14, 3242-3253. Cited 25.
- Pelin, K., Hilpelä, P., Donner, K., Sewry, C., Akkari, P.A., Wilton, S.D., Wattanasirichaigoon, D., Bang, M.L., Centner, T., Hanefeld, F., Odent, S., Fardeau, M., Urtizberea, J.A., Muntoni, F., Dubowitz, V., Beggs, A.H., Laing, N.G., Labeit, S., de la Chapelle, A., and Wallgren-Pettersson, C. (1999) Mutations in the nebulin gene associated with autosomal recessive nemaline myopathy. Proc. Natl. Acad. U.S.A.96, 2305-2310. Cited 198.
- Wallgren-Pettersson, C., Pelin, K., Hilpelä, P., Donner, K., Porfirio, B., Graziano, C., Swoboda, K.J., Fardeau, M., Urtizberea, J.A., Muntoni, F., Sewry, C., Dubowitz, V., Iannaccone, S., Minetti, C., Pedemonte, M., Seri, M., Cusano, R., Lammens, M., Castagna-Sloane, A., Beggs, A.H., Laing, N.G., and de la Chapelle, A. (1999) Clinical and genetic heterogeneity in autosomal recessive nemaline myopathy. Neuromuscul. Disord 9, 564-572. Cited 65.