Intramolecular disulfide bonds of the prolactin receptor short form are required for its inhibitory action on the function of the long form of the receptor.

ABSTRACT: The short form (S1b) of the prolactin receptor (PRLR) silences prolactin-induced activation of gene transcription by the PRLR long form (LF). The functional and structural contributions of two intramolecular disulfide (S-S) bonds within the extracellular subdomain 1 (D1) of S1b to its inhibitory function on the LF were investigated. Mutagenesis of the paired cysteines eliminated the inhibitory action of S1b. The expression of the mutated S1b (S1bx) on the cell surface was not affected, indicating native-like folding of the receptor. The constitutive JAK2 phosphorylation observed in S1b was not present in cells expressing S1bx, and JAK2 association was disrupted. BRET(50) (BRET(50) represents the relative affinity as acceptor/donor ratio required to reach half-maximal BRET [bioluminescence

SUBMITTER: Xie YL 

PROVIDER: S-EPMC2682051 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature