TY - JOUR
T1 - SksC, a fertilization-related protein kinase in chlamydomonas, is expressed throughout the cell cycle and gametogenesis, and a phosphorylated form is present in both flagella and cell bodies
AU - Kurvari, Venkatesh
AU - Snell, William J.
N1 - Funding Information:
We thank Ms. Katrina Emmett for technical assistance in the affinity-purification of anti-SksC antibodies, and Dr. Fred Grinnell for his comments during the preparation of this manuscript. This work was supported by the National Institutes of Health grant GM25661 to W.J.S.
PY - 1996/11/1
Y1 - 1996/11/1
N2 - Fertilization in the biflagellated eukaryote, Chlamydomonas, is initiated by flagellar adhesion between gametes of opposite mating types. An early event in the signal transduction pathway induced by these cell-cell interactions is the rapid inactivation of a flagellar protein kinase that phosphorylates a 48 kDa flagellar protein. Molecular cloning and characterization indicated that the 48 kDa substrate, termed SksC, itself is a novel protein kinase. Here, we have determined that its transcript levels were unchanged during prolonged flagellar adhesion. Moreover, resynthesis of new flagellar proteins following deflagellation was not accompanied by increases in transcript levels of SksC, suggesting that expression of this soluble protein kinase might not be restricted to flagella. Immunoblot analysis indicated that expression of SksC was ubiquitous: this soluble protein was found in both flagella and cell bodies and was expressed throughout the cell cycle and gametogenesis. Immunoprecipitation experiments indicated that SksC was phosphorylated in both flagella and cell bodies. Thus, in addition to its potential role in fertilization, this novel protein kinase may play a role in other signaling events in Chlamydomonas.
AB - Fertilization in the biflagellated eukaryote, Chlamydomonas, is initiated by flagellar adhesion between gametes of opposite mating types. An early event in the signal transduction pathway induced by these cell-cell interactions is the rapid inactivation of a flagellar protein kinase that phosphorylates a 48 kDa flagellar protein. Molecular cloning and characterization indicated that the 48 kDa substrate, termed SksC, itself is a novel protein kinase. Here, we have determined that its transcript levels were unchanged during prolonged flagellar adhesion. Moreover, resynthesis of new flagellar proteins following deflagellation was not accompanied by increases in transcript levels of SksC, suggesting that expression of this soluble protein kinase might not be restricted to flagella. Immunoblot analysis indicated that expression of SksC was ubiquitous: this soluble protein was found in both flagella and cell bodies and was expressed throughout the cell cycle and gametogenesis. Immunoprecipitation experiments indicated that SksC was phosphorylated in both flagella and cell bodies. Thus, in addition to its potential role in fertilization, this novel protein kinase may play a role in other signaling events in Chlamydomonas.
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U2 - 10.1006/bbrc.1996.1614
DO - 10.1006/bbrc.1996.1614
M3 - Article
C2 - 8912634
AN - SCOPUS:0030296856
SN - 0006-291X
VL - 228
SP - 45
EP - 54
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -