Prolactin-like protein-C variant: complementary deoxyribonucleic acid, unique six exon gene structure, and trophoblast cell-specific expression.
The rat placental PRL family consists of proteins structurally related to pituitary PRL. As a consequence of attempting to characterize the gene for one of the members of the family, PRL-like protein-C (PLP-C), we identified a related gene that we have termed PLP-C variant (PLP-Cv). In this study, we present information on the PLP-Cv gene and its pattern of expression. Screening of a rat genomic library with a PLP-C cDNA resulted in the isolation of four phage clones. Nucleotide sequence analysis of the clones revealed a gene, PLP-Cv, closely related but distinct from PLP-C. The PLP-Cv gene possessed a six exon/five intron organization, unique among members of the PRL family, and was localized to chromosome 17 of the rat genome, similar to other PRL family members. A PCR strategy involving primers based on the PLP-Cv gene was used to isolate a placental PLP-Cv cDNA. PLP-Cv showed 90 and 78% sequence identity with PLP-C at nucleotide and amino acid levels, respectively. Expression of PLP-Cv was restricted to the trophoblast lineage and was coordinately activated with PLP-C beginning at day 11 of gestation and continuing until term. Primer extension analysis revealed multiple putative transcription start sites. A 2.1-kilobase pair PLP-Cv promoter-luciferase reporter construct was specifically activated in differentiating rat trophoblast cells but not in other cell types. In conclusion, we have identified a new member of the PRL family possessing considerable homology to PLP-C, a unique gene structure, and displaying a trophoblast-specific pattern of transcriptional activation.
Dai
G
G
Department of Physiology, University of Kansas Medical Center, Kansas City 66160, USA.
Liu
B
B
Szpirer
C
C
Levan
G
G
Kwok
S C
SC
Soares
M J
MJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002874:Chromosome Mapping; D017931:DNA Primers; D018076:DNA, Complementary; D003656:Decidua / Q000378:metabolism*; D005091:Exons; D005260:Female; D015870:Gene Expression; D015698:Genomic Library; D006822:Hybrid Cells; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D011401:Promoter Regions, Genetic; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D015203:Reproducibility of Results; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014327:Trophoblasts / Q000378:metabolism*
D017931:DNA Primers; D018076:DNA, Complementary; D011257:Pregnancy Proteins; C502145:Prl8a3 protein, rat; C502144:Prlpc1 protein, mouse; C502146:Prlpc2 protein, mouse; C502147:Prlpc3 protein, mouse; D011994:Recombinant Proteins