PMID- 10588661
OWN - NLM
STAT- MEDLINE
DCOM- 20000214
LR  - 20190508
IS  - 1059-1524 (Print)
IS  - 1059-1524 (Linking)
VI  - 10
IP  - 12
DP  - 1999 Dec
TI  - Espin contains an additional actin-binding site in its N terminus and is a major 
      actin-bundling protein of the Sertoli cell-spermatid ectoplasmic specialization
      junctional plaque.
PG  - 4327-39
AB  - The espins are actin-binding and -bundling proteins localized to parallel actin
      bundles. The 837-amino-acid "espin" of Sertoli cell-spermatid junctions
      (ectoplasmic specializations) and the 253-amino-acid "small espin" of brush
      border microvilli are splice isoforms that share a C-terminal 116-amino-acid
      actin-bundling module but contain different N termini. To investigate the roles
      of espin and its extended N terminus, we examined the actin-binding and -bundling
      properties of espin constructs and the stoichiometry and developmental
      accumulation of espin within the ectoplasmic specialization. An espin construct
      bound to F-actin with an approximately threefold higher affinity (K(d) =
      approximately 70 nM) than small espin and was approximately 2.5 times more
      efficient at forming bundles. The increased affinity appeared to be due to an
      additional actin-binding site in the N terminus of espin. This additional
      actin-binding site bound to F-actin with a K(d) of approximately 1 microM,
      decorated actin stress fiber-like structures in transfected cells, and was mapped
      to a peptide between the two proline-rich peptides in the N terminus of espin.
      Espin was detected at approximately 4-5 x 10(6) copies per ectoplasmic
      specialization, or approximately 1 espin per 20 actin monomers and accumulated
      there coincident with the formation of parallel actin bundles during
      spermiogenesis. These results suggest that espin is a major actin-bundling
      protein of the Sertoli cell-spermatid ectoplasmic specialization.
FAU - Chen, B
AU  - Chen B
AD  - Department of Cell and Molecular Biology, Northwestern University Medical School,
      Chicago, Illinois 60611, USA.
FAU - Li, A
AU  - Li A
FAU - Wang, D
AU  - Wang D
FAU - Wang, M
AU  - Wang M
FAU - Zheng, L
AU  - Zheng L
FAU - Bartles, J R
AU  - Bartles JR
LA  - eng
SI  - GENBANK/AF134858
GR  - K02 HD-01210/HD/NICHD NIH HHS/United States
GR  - R01 HD-35280/HD/NICHD NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Mol Biol Cell
JT  - Molecular biology of the cell
JID - 9201390
RN  - 0 (Actins)
RN  - 0 (Microfilament Proteins)
RN  - 0 (Protein Isoforms)
RN  - 0 (Recombinant Proteins)
RN  - 0 (espin protein, mouse)
SB  - IM
MH  - Actins/chemistry/*metabolism
MH  - Animals
MH  - Binding Sites
MH  - Male
MH  - Mice
MH  - Microfilament Proteins/chemistry/genetics/*metabolism
MH  - Microscopy, Immunoelectron
MH  - Protein Binding
MH  - Protein Isoforms/chemistry/genetics/metabolism
MH  - Recombinant Proteins/metabolism
MH  - Seminiferous Tubules/metabolism/ultrastructure
MH  - Sertoli Cells/*metabolism/ultrastructure
MH  - Spermatids/*metabolism
PMC - PMC25761
EDAT- 1999/12/10 09:00
MHDA- 2000/02/19 09:00
CRDT- 1999/12/10 09:00
PHST- 1999/12/10 09:00 [pubmed]
PHST- 2000/02/19 09:00 [medline]
PHST- 1999/12/10 09:00 [entrez]
AID - 10.1091/mbc.10.12.4327 [doi]
PST - ppublish
SO  - Mol Biol Cell. 1999 Dec;10(12):4327-39. doi: 10.1091/mbc.10.12.4327.