The aquaporins (AQPs) are a family of small, hydrophobic, integral membrane proteins that allow rapid water transport across the cell membrane. Relatively few reports about AQPs in non-mammalian vertebrates exist. AQP homologous have been reported in some teleosts such as the sea bream, sea bass and eel. At the best of our knowledge, until now there is no information regarding the expression of aquaporins in fish spermatozoa. Here we show that 0.01, 0.1 and 1 mM HgCl2 (known aquaporin inhibitor) completely inhibited sperm motility, a 0.001 mM concentration was ineffective. In addition, using the RT-PCR technique, we demonstrated the presence of aquaglyceroporin mRNA in sea bream and sea bass spermatozoa. Primers used in the RT-PCR were designed for sea bream aquaglyceroporin (AY363261). The sequencing of PCR products of the expected size (213 bp) revealed that this portion of aquaporin of sea bream and sea bass sperm have an homology of 100% with that of gilthead sea bream hind-gut. The presence of AQP in sea bream and sea bass spermatozoa was also confirmed by Western blot experiments. All together our findings allow us to hypothesize that in both sea bream and sea bass sperm AQPs are involved in sperm motility initiation mechanisms.
Expression of aquaglyceroporin in spermatozoa of two marine fish (sparus aurata and dicentrarchus labrax)
ZILLI, Loredana;SCHIAVONE, Roberta;STORELLI, Carlo;VILELLA, Sebastiano
2008-01-01
Abstract
The aquaporins (AQPs) are a family of small, hydrophobic, integral membrane proteins that allow rapid water transport across the cell membrane. Relatively few reports about AQPs in non-mammalian vertebrates exist. AQP homologous have been reported in some teleosts such as the sea bream, sea bass and eel. At the best of our knowledge, until now there is no information regarding the expression of aquaporins in fish spermatozoa. Here we show that 0.01, 0.1 and 1 mM HgCl2 (known aquaporin inhibitor) completely inhibited sperm motility, a 0.001 mM concentration was ineffective. In addition, using the RT-PCR technique, we demonstrated the presence of aquaglyceroporin mRNA in sea bream and sea bass spermatozoa. Primers used in the RT-PCR were designed for sea bream aquaglyceroporin (AY363261). The sequencing of PCR products of the expected size (213 bp) revealed that this portion of aquaporin of sea bream and sea bass sperm have an homology of 100% with that of gilthead sea bream hind-gut. The presence of AQP in sea bream and sea bass spermatozoa was also confirmed by Western blot experiments. All together our findings allow us to hypothesize that in both sea bream and sea bass sperm AQPs are involved in sperm motility initiation mechanisms.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
