Open AccessType V myosin focuses the polarisome and shapes the tip of yeast cells
Author(s) -
Alexander Dünkler,
Marcin Leda,
Jan-Michael Kromer,
Joachim Neller,
Thomas Gronemeyer,
Andrew B. Goryachev,
Nils Johnsson
Publication year - 2021
Publication title -
the journal of cell biology/the journal of cell biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.414
H-Index - 380
eISSN - 1540-8140
pISSN - 0021-9525
DOI - 10.1083/jcb.202006193
Subject(s) - biology , myosin , actin , protein subunit , yeast , microbiology and biotechnology , secretory vesicle , model organism , mutation , saccharomyces cerevisiae , vesicle , biophysics , genetics , gene , membrane
The polarisome is a cortical proteinaceous microcompartment that organizes the growth of actin filaments and the fusion of secretory vesicles in yeasts and filamentous fungi. Polarisomes are compact, spotlike structures at the growing tips of their respective cells. The molecular forces that control the form and size of this microcompartment are not known. Here we identify a complex between the polarisome subunit Pea2 and the type V Myosin Myo2 that anchors Myo2 at the cortex of yeast cells. We discovered a point mutation in the cargo-binding domain of Myo2 that impairs the interaction with Pea2 and consequently the formation and focused localization of the polarisome. Cells carrying this mutation grow round instead of elongated buds. Further experiments and biophysical modeling suggest that the interactions between polarisome-bound Myo2 motors and dynamic actin filaments spatially focus the polarisome and sustain its compact shape.