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Microgravity alters protein phosphorylation changes during initiation of sea urchin sperm motility
Author(s) -
Tash Joseph S.,
Bracho Gerácimo E.
Publication year - 1999
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.13.9001.s43
Subject(s) - phosphorylation , sperm , sperm motility , motility , sea urchin , protein phosphorylation , biology , human fertilization , phosphoserine , microbiology and biotechnology , chemistry , biochemistry , protein kinase a , serine , anatomy , botany
European Space Agency (ESA) studies demonstrated that bull sperm swim with higher velocity in microgravity (µG) than at 1 G. Coupling between protein phosphorylation and sperm motility during activation in µG and at 1 G was examined in the ESA Biorack on two space shuttle missions. Immotile sperm were activated to swim (86–90% motility) at launch +20 h by dilution into artificial seawater (ASW). Parallel ground controls were performed 2 h after the flight experiment. Activation after 0, 30, and 60 s was terminated with electrophoresis sample buffer and samples analyzed for phosphoamino acids by Western blotting. Phosphorylation of a 130‐kDa phosphothreonine‐containing protein (FP130) occurred three to four times faster in µG than at 1 G. A 32‐kDa phosphoserine‐containing protein was significantly stimulated at 30 s but returned to 1 G control levels at 60 s. The rate of FP130 phosphorylation in µG was attenuated by D 2 O, suggesting that changes in water properties participate in altering signal transduction. Changes in FP130 phosphorylation triggered by the egg peptide speract were delayed in µG. These results demonstrate that previously observed effects of µG on sperm motility are coupled to changes in phosphorylation of specific flagellar proteins and that early events of sperm activation and fertilization are altered in µG.—Tash, J. S., Bracho, G. E. Microgravity alters protein phosphorylation changes during initiation of sea urchin sperm motility. FASEB J. 13 (Suppl.), S43–S54 (1999)