TY - JOUR
T1 - The glycolytic enzyme enolase is present in sperm tail and displays nucleotide-dependent association with microtubes
AU - Gitlits, Veronika M.
AU - Toh, Ban Hock
AU - Loveland, Kate Lakoski
AU - Sentry, John W.
PY - 2000/1/1
Y1 - 2000/1/1
N2 - We examined the expression and localisation of enolase (2-phospho-D-glycerate hydrolase) in differentiating rat spermatogenic cells. We found that enolase is most abundant in mature spermatozoa and in residual cytoplasmic bodies detached from elongating spermatids with little to no enolase detected in meiotic primary spermatocytes and round spermatids. We localised enolase mostly to the tail of mature spermatozoa by immunoblotting and by immunofluorescence. RT-PCR analysis of differentiating spermatogenic cells detected only the α isoform of enolase. As several glycolytic enzymes are known to associate with microtubules prepared from brain, we investigated the association of enolase with brain and testis microtubules. We found that only a small fraction of testis and brain-derived cytosolic enolase (4.9% and 11.2%, respectively) co-sediments with microtubules stabilised in the presence of taxol. In the presence of certain nucleotides in excess (3 mM ATP, CTP, GTP and ITP) the association of enolase with microtubules was disrupted, however, this was not the case for UTP. This observation is consistent with the finding that in the presence of 0.5 mM AMP-PNP, a non-hydrolysable analogue of ATP, there is an increased association of enolase with microtubules. We propose that the nucleotide-dependent association of enolase with microtubules regulates enzyme activity by linking energy production to utilisation.
AB - We examined the expression and localisation of enolase (2-phospho-D-glycerate hydrolase) in differentiating rat spermatogenic cells. We found that enolase is most abundant in mature spermatozoa and in residual cytoplasmic bodies detached from elongating spermatids with little to no enolase detected in meiotic primary spermatocytes and round spermatids. We localised enolase mostly to the tail of mature spermatozoa by immunoblotting and by immunofluorescence. RT-PCR analysis of differentiating spermatogenic cells detected only the α isoform of enolase. As several glycolytic enzymes are known to associate with microtubules prepared from brain, we investigated the association of enolase with brain and testis microtubules. We found that only a small fraction of testis and brain-derived cytosolic enolase (4.9% and 11.2%, respectively) co-sediments with microtubules stabilised in the presence of taxol. In the presence of certain nucleotides in excess (3 mM ATP, CTP, GTP and ITP) the association of enolase with microtubules was disrupted, however, this was not the case for UTP. This observation is consistent with the finding that in the presence of 0.5 mM AMP-PNP, a non-hydrolysable analogue of ATP, there is an increased association of enolase with microtubules. We propose that the nucleotide-dependent association of enolase with microtubules regulates enzyme activity by linking energy production to utilisation.
KW - Enolase
KW - Glycolytic enzyme
KW - Microtubules
KW - Nucleotides
KW - Spermatogenesis
KW - Taxol
UR - http://www.scopus.com/inward/record.url?scp=0034100185&partnerID=8YFLogxK
U2 - 10.1078/S0171-9335(04)70012-6
DO - 10.1078/S0171-9335(04)70012-6
M3 - Article
C2 - 10727018
AN - SCOPUS:0034100185
VL - 79
SP - 104
EP - 111
JO - European Journal of Cell Biology
JF - European Journal of Cell Biology
SN - 0171-9335
IS - 2
ER -