Sequence of the 3′-noncoding region of the luteinizing hormone receptor gene and identification of two polyadenylation domains that generate the major mRNA forms

Abstract

We present 6.2 kb of the 3′-noncoding region sequence of the rat luteinizing hormone receptor (LHR) gene and identification of two functional polyadenylation (pA) domains, H1 (nt 2368–2491) and H2 (nt 5579–5768) responsible for 3′-end processing of the 2.6 2.3 kb and the 5.8 kb LHR mRNA, respectively. Two identical copies of pA elements AAUAUA in H1 and of AAUAAA in H2 account for micro-heterogeneous poly(A) addition at each of the two pA regions. Both LH holoreceptor and major splice variant form B (lacking the first 266 bp of exon 11) are identified in H1-terminated (2.6 kb and 2.3 kb) and H2-terminated (5.8 kb) mRNA transcripts. A rodent repetitive DNA LINE R domain 3′ of H1 within the major 5.8 kb species and a B2 element downstream of H2 were identified. Alignment of the 3′-noncoding region of LHR with TSH, FSH and β 2-adrenergic receptors indicate that H1 pA signal is unique to the LHR and may represent an insertion domain.