RRC ID 2222
Author Itadani A, Nakamura T, Shimoda C.
Title Localization of type I myosin and F-actin to the leading edge region of the forespore membrane in Schizosaccharomyces pombe.
Journal Cell Struct Funct
Abstract Myo1, a heavy chain of type I myosin of the fission yeast Schizosaccharomyces pombe, is essential for sporulation. Here we have analyzed the expression, localization and cellular function of the type I myosin light chain calmodulin, Cam2, encoded by cam2(+). Transcription of cam2(+) was constitutive and markedly enhanced in meiosis. The cam2 null mutant was viable and completed sporulation normally at 28 degrees C, but formed four-spored asci poorly at 34 degrees C. In those sporulation-defective cells, the forespore membrane was formed abnormally. A Cam2-GFP fusion protein accumulated at the cell poles in interphase cells and at the medial septation site in postmitotic cells, colocalizing with Myo1 and F-actin patches. During the mating process, a single Cam2-GFP dot was detected at the tip of the mating projection. During meiosis-I, the Cam2-GFP dots dispersed into the cell periphery and the cytoplasm. At metaphase-II, intense Cam2-GFP signals appeared near Meu14 rings which were formed at the leading edge of expanding forespore membranes. This localization of Cam2 was dependent upon Myo1; and sporulation defect of cam2Delta at 34 degrees C was alleviated by overexpressing Myo1DeltaIQ. These results suggest a close relationship between Cam2 and Myo1. In addition, both F-actin and Myo1 localized with Cam2 in the leading edge region. In summary, type I myosin and F-actin accumulate at the leading edge area of the forespore membrane and may play a pivotal role in its assembly.
Volume 31(2)
Pages 181-95
Published 2006-1-1
DOI 10.1247/csf.06027
PII JST.JSTAGE/csf/06027
PMID 17202724
MeSH Actins / genetics Actins / metabolism* Amino Acid Sequence Calmodulin / analysis Calmodulin / genetics Calmodulin / metabolism* Cell Membrane / metabolism* Gene Expression Regulation, Fungal Molecular Sequence Data Mutation / genetics Myosin Type I / genetics Myosin Type I / metabolism* Phenotype RNA, Messenger / metabolism Schizosaccharomyces / metabolism* Schizosaccharomyces pombe Proteins / analysis Schizosaccharomyces pombe Proteins / metabolism* Spores, Fungal / chemistry Spores, Fungal / metabolism*
IF 2.429
Times Cited 15
Yeast FY7132 FY7051 FY7476 FY12492 FY12710