A truncated P2X7 receptor variant (P2X7-j) endogenously expressed in cervical cancer cells antagonizes the full-length P2X7 receptor through hetero-oligomerization.

ABSTRACT: A truncated naturally occurring variant of the human receptor P2X7 was identified in cancer cervical cells. The novel protein (P2X7-j), a polypeptide of 258 amino acids, lacks the entire intracellular carboxyl terminus, the second transmembrane domain, and the distal third of the extracellular loop of the full-length P2X7 receptor. The P2X7-j was expressed in the plasma membrane; it showed diminished ligand-binding and channel function capacities and failed to form pores and mediate apoptosis in response to treatment with the P2X7 receptor agonist benzoyl-ATP. The P2X7-j interacted with the full-length P2X7 in a manner suggesting heterooligomerization and blocked the P2X7-mediated actions. Interestingly, P2X7-j immunoreactivity and mRNA expression were similar in lysates of human cancer an

SUBMITTER: Feng YH 

PROVIDER: S-EPMC2409001 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature