TY - JOUR
T1 - A novel germ cell protein, SPIF (sperm PKA interacting factor), is essential for the formation of a PKA/TCP11 complex that undergoes conformational and phosphorylation changes upon capacitation
AU - Stanger, Simone J.
AU - Law, Estelle A.
AU - Jamsai, Duangporn
AU - O'Bryan, Moira K.
AU - Nixon, Brett
AU - McLaughlin, Eileen A.
AU - Aitken, R. John
AU - Roman, Shaun D.
PY - 2016/8/1
Y1 - 2016/8/1
N2 - Spermatozoa require the process of capacitation to enable them to fertilize an egg. PKA is crucial to capacitation and the development of hyperactivated motility. Sperm PKA is activated by cAMP generated by the germ cell-enriched adenylyl cyclase encoded by Adcy10. Male mice lacking Adcy10 are sterile, because their spermatozoa are immotile. The current studywas designed to identify binding partners of the sperm-specific (Cα2) catalytic subunit of PKA (PRKACA) by using it as the "bait" in a yeast 2-hybrid system. This approach was used to identify a novel germ cell-enriched protein, sperm PKA interacting factor (SPIF), in 25% of the positive clones. Homozygous Spif-nullmice were embryonically lethal. SPIF was coexpressed and coregulated with PRKACA and with t-complex protein (TCP)-11, a protein associated with PKA signaling. We established that these 3 proteins form part of a novel complex in mouse spermatozoa. Upon capacitation, the SPIF protein becomes tyrosine phosphorylatedin > 95% of sperm. Anapparent molecular rearrangement in the complex occurs, bringing PRKACA and TCP11 into proximity. Taken together, these results suggest a role for the novel complex of SPIF, PRKACA, and TCP11 during spermcapacitation, fertilization, and embryogenesis.
AB - Spermatozoa require the process of capacitation to enable them to fertilize an egg. PKA is crucial to capacitation and the development of hyperactivated motility. Sperm PKA is activated by cAMP generated by the germ cell-enriched adenylyl cyclase encoded by Adcy10. Male mice lacking Adcy10 are sterile, because their spermatozoa are immotile. The current studywas designed to identify binding partners of the sperm-specific (Cα2) catalytic subunit of PKA (PRKACA) by using it as the "bait" in a yeast 2-hybrid system. This approach was used to identify a novel germ cell-enriched protein, sperm PKA interacting factor (SPIF), in 25% of the positive clones. Homozygous Spif-nullmice were embryonically lethal. SPIF was coexpressed and coregulated with PRKACA and with t-complex protein (TCP)-11, a protein associated with PKA signaling. We established that these 3 proteins form part of a novel complex in mouse spermatozoa. Upon capacitation, the SPIF protein becomes tyrosine phosphorylatedin > 95% of sperm. Anapparent molecular rearrangement in the complex occurs, bringing PRKACA and TCP11 into proximity. Taken together, these results suggest a role for the novel complex of SPIF, PRKACA, and TCP11 during spermcapacitation, fertilization, and embryogenesis.
KW - Protein complex
KW - Protein kinase A
KW - Sperm capacitation
KW - Tyrosine kinase
KW - Spermatozoa/physiology
KW - Protein Subunits
KW - Phosphorylation
KW - Membrane Proteins/genetics
KW - Male
KW - Cyclic AMP-Dependent Protein Kinases/genetics
KW - RNA, Messenger/genetics
KW - Sex Ratio
KW - Sperm Capacitation/physiology
KW - Two-Hybrid System Techniques
KW - Animals
KW - Carrier Proteins/genetics
KW - Protein Isoforms
KW - Female
KW - Heterozygote
KW - Protein Conformation
KW - Mice
KW - Gene Expression Regulation/physiology
UR - http://www.scopus.com/inward/record.url?scp=84982719868&partnerID=8YFLogxK
UR - http://www.mendeley.com/research/novel-germ-cell-protein-spif-sperm-pka-interacting-factor-essential-formation-pkatcp11-complex-under
U2 - 10.1096/fj.201500136R
DO - 10.1096/fj.201500136R
M3 - Article
C2 - 27105888
AN - SCOPUS:84982719868
SN - 0892-6638
VL - 30
SP - 2777
EP - 2791
JO - FASEB Journal
JF - FASEB Journal
IS - 8
ER -