Cell biology. A universal bicarbonate sensor.
The life-span of sperm may be short but it is certainly busy. The three principal molecular events that prepare sperm for fertilization are all controlled by the intracellular nucleotide adenosine 3',5'-monophosphate (cAMP). One of these, capacitation, is also regulated by bicarbonate ions. The elusive connection between cAMP and bicarbonate ions now appears to be solved as Kaupp and Weyand explain in their Perspective. Bicarbonate ions enter sperm through the anion transporter in the sperm plasma membrane and activate the soluble form of adenylyl cyclase, the enzyme that synthesizes cAMP (Chen et al.)
Kaupp
U B
UB
Biologische Informationsverarbeitung, Forschungszentrum Jlich, Germany.
Weyand
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I
D000262:Adenylyl Cyclases / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism* / Q000494:pharmacology; D015220:Calcium Channels / Q000378:metabolism; D020134:Catalytic Domain; D000242:Cyclic AMP / Q000378:metabolism*; D054815:Cyclic Nucleotide-Gated Cation Channels; D004789:Enzyme Activation; D006801:Humans; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D009124:Muscle Proteins; D015221:Potassium Channels; D051381:Rats; D015398:Signal Transduction; D012995:Solubility; D013075:Sperm Capacitation; D013081:Sperm Motility; D013082:Sperm Tail / Q000502:physiology; D013094:Spermatozoa / Q000378:metabolism / Q000502:physiology*
D001639:Bicarbonates; D015220:Calcium Channels; D054815:Cyclic Nucleotide-Gated Cation Channels; C119587:HCN4 protein, human; D064428:Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels; D007473:Ion Channels; D009124:Muscle Proteins; D015221:Potassium Channels; D000242:Cyclic AMP; D000262:Adenylyl Cyclases