PMID- 10591629
OWN - NLM
STAT- MEDLINE
DCOM- 20000302
LR  - 20071115
IS  - 0021-9533 (Print)
IS  - 0021-9533 (Linking)
VI  - 113 ( Pt 1)
DP  - 2000 Jan
TI  - Ropporin, a sperm-specific binding protein of rhophilin, that is localized in the
      fibrous sheath of sperm flagella.
PG  - 103-12
AB  - The small GTPase Rho; functions as a molecular switch that regulates various
      cellular processes such as cell adhesion, motility, gene expression and
      cytokinesis. We previously isolated several putative Rho; targets including
      rhophilin which bound selectively to the GTP-bound form of Rho;. Rhophilin is
      expressed highly in testis and is localized specifically in sperm flagella. The
      presence of a PDZ domain at the carboxy terminus of rhophilin suggested that
      rhophilin works as an adaptor molecule. To test this hypothesis, we employed a
      yeast two hybrid system using the rhophilin PDZ domain as a bait, and screened a 
      mouse testis cDNA library. We isolated several positive clones containing the
      same insert. The open reading frame of the cDNA encoded a novel protein of 212
      amino acids designated as ropporin from a Japanese word 'oppo' (the tail). The
      amino-terminal 40 amino acid sequence of ropporin showed high homology to that of
      the regulatory subunit of type II cAMP-dependent protein kinase, which is
      involved in dimerization and binding to A-kinase anchoring proteins.
      Consistently, a yeast two hybrid assay and gel filtration of recombinant ropporin
      indicated that ropporin dimerizes through this domain. Deletion analysis
      indicated that the carboxy-terminal four amino acids are essential for binding of
      ropporin to rhophilin, and ropporin and RhoV14 coprecipitated in the presence of 
      rhophilin in vitro. Northern blot analysis showed that ropporin is exclusively
      expressed in testis, and induced at the late stage of spermatogenesis. This
      induction paralleled that of rhophilin. Immunocytochemistry using anti-ropporin
      antibody showed that ropporin is localized in the principal piece and the end
      piece of sperm flagella. Electronmicroscopy revealed that ropporin is mostly
      localized in the inner surface of the fibrous sheath while rhophilin is present
      in the outer surface of the outer dense fiber. These results suggest that
      rhophilin and ropporin may form a complex in sperm flagella.
FAU - Fujita, A
AU  - Fujita A
AD  - Department of Pharmacology and Department of Anatomy and Neurobiology, Kyoto
      University Faculty of Medicine, Sakyo, Kyoto 606-8501, Japan.
FAU - Nakamura, K
AU  - Nakamura K
FAU - Kato, T
AU  - Kato T
FAU - Watanabe, N
AU  - Watanabe N
FAU - Ishizaki, T
AU  - Ishizaki T
FAU - Kimura, K
AU  - Kimura K
FAU - Mizoguchi, A
AU  - Mizoguchi A
FAU - Narumiya, S
AU  - Narumiya S
LA  - eng
SI  - GENBANK/AF178531
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - J Cell Sci
JT  - Journal of cell science
JID - 0052457
RN  - 0 (Adaptor Proteins, Signal Transducing)
RN  - 0 (Membrane Proteins)
RN  - 0 (RNA, Messenger)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 0 (Ropn1 protein, mouse)
RN  - 0 (rhophilin)
RN  - EC 2.7.11.1 (Protein-Serine-Threonine Kinases)
RN  - EC 2.7.11.11 (Cyclic AMP-Dependent Protein Kinase Type II)
RN  - EC 2.7.11.11 (Cyclic AMP-Dependent Protein Kinases)
RN  - EC 3.6.5.2 (rho GTP-Binding Proteins)
SB  - IM
MH  - Adaptor Proteins, Signal Transducing
MH  - Amino Acid Sequence
MH  - Animals
MH  - Base Sequence
MH  - Binding Sites
MH  - COS Cells
MH  - Cloning, Molecular
MH  - Cyclic AMP-Dependent Protein Kinase Type II
MH  - Cyclic AMP-Dependent Protein Kinases/chemistry
MH  - Dimerization
MH  - Male
MH  - *Membrane Proteins
MH  - Mice
MH  - Microscopy, Immunoelectron
MH  - Molecular Sequence Data
MH  - Protein Binding
MH  - Protein-Serine-Threonine Kinases/chemistry/genetics/*metabolism
MH  - RNA, Messenger/genetics/metabolism
MH  - Recombinant Fusion Proteins/chemistry/genetics/metabolism
MH  - Sequence Deletion/genetics
MH  - Sequence Homology, Amino Acid
MH  - Sperm Tail/chemistry/*metabolism/ultrastructure
MH  - Spermatogenesis/genetics
MH  - Testis/chemistry/cytology/metabolism
MH  - Two-Hybrid System Techniques
MH  - rho GTP-Binding Proteins/chemistry/genetics/*metabolism
EDAT- 1999/12/11 09:00
MHDA- 2000/03/04 09:00
CRDT- 1999/12/11 09:00
PHST- 1999/12/11 09:00 [pubmed]
PHST- 2000/03/04 09:00 [medline]
PHST- 1999/12/11 09:00 [entrez]
PST - ppublish
SO  - J Cell Sci. 2000 Jan;113 ( Pt 1):103-12.