Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-8-27
pubmed:abstractText
Recent evidence indicates the presence of p21 Ras and of a protein with characteristics similar to mitogen-activated protein kinases (MAPKs), also known as extracellular signal-regulated kinases (ERKs), in mammalian spermatozoa, suggesting the occurrence of the Ras/ERK cascade in these cells. In the present study we investigated the subcellular localization of ERKs and their biological functions in human spermatozoa. Immunohistochemistry, immunofluorescence, confocal microscopy, and immunoelectron microscopy demonstrated localization of ERKs in the postacrosomal region of spermatozoa. After stimulation of acrosome reaction with the calcium ionophore A23187 and progesterone, ERKs were mostly localized at the level of the equatorial region, indicating redistribution of these proteins in acrosome-reacted spermatozoa. Two proteins of 42 and 44 kDa that are tyrosine phosphorylated in a time-dependent manner during in vitro capacitation were identified as p42 (ERK-2) and p44 (ERK-1) by means of specific antibodies. The increase in tyrosine phosphorylation of these proteins during capacitation was accompanied by increased kinase activity, as determined by the ability of ERK-1 and ERK-2 to phosphorylate the substrate myelin basic protein. The role of this activity in the occurrence of sperm capacitation was also investigated by using PD098059, an inhibitor of the MAPK cascade. The presence of this compound during in vitro capacitation inhibits ERK activation and significantly reduces the ability of spermatozoa to undergo the acrosome reaction in response to progesterone. Since only capacitated spermatozoa are able to respond to progesterone, these data strongly indicate that ERKs are involved in the regulation of capacitation. In summary, our data demonstrate the presence of functional ERKs in human spermatozoa and indicate that these enzymes are involved in activation of these cells during capacitation, providing new insight in clarifying the molecular mechanisms and the signal transduction pathways of this process.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Calcimycin, http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Calmodulin-Dependent..., http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Flavonoids, http://linkedlifedata.com/resource/pubmed/chemical/Ionophores, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase 1, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase 3, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase..., http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/PD 98059, http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Tyrosine
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1476-89
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:9623609-Acrosome, pubmed-meshheading:9623609-Adult, pubmed-meshheading:9623609-Calcimycin, pubmed-meshheading:9623609-Calcium-Calmodulin-Dependent Protein Kinases, pubmed-meshheading:9623609-Enzyme Inhibitors, pubmed-meshheading:9623609-Flavonoids, pubmed-meshheading:9623609-Fluorescent Antibody Technique, pubmed-meshheading:9623609-Humans, pubmed-meshheading:9623609-Immunohistochemistry, pubmed-meshheading:9623609-Ionophores, pubmed-meshheading:9623609-Male, pubmed-meshheading:9623609-Microscopy, Confocal, pubmed-meshheading:9623609-Microscopy, Immunoelectron, pubmed-meshheading:9623609-Mitogen-Activated Protein Kinase 1, pubmed-meshheading:9623609-Mitogen-Activated Protein Kinase 3, pubmed-meshheading:9623609-Mitogen-Activated Protein Kinase Kinases, pubmed-meshheading:9623609-Mitogen-Activated Protein Kinases, pubmed-meshheading:9623609-Phosphorylation, pubmed-meshheading:9623609-Protein Kinase Inhibitors, pubmed-meshheading:9623609-Sperm Capacitation, pubmed-meshheading:9623609-Spermatozoa, pubmed-meshheading:9623609-Testis, pubmed-meshheading:9623609-Tyrosine
pubmed:year
1998
pubmed:articleTitle
Extracellular signal-regulated kinases modulate capacitation of human spermatozoa.
pubmed:affiliation
Dipartimento di Fisiopatologia Clinica, Universita' di Firenze, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't