Cloning of two novel growth hormone transcripts expressed in human placenta

被引:42
作者
Boguszewski, CL
Svensson, PA
Jansson, T
Clark, R
Carlsson, LMS
Carlsson, B
机构
[1] Sahlgrens Univ Hosp, Res Ctr Endocrinol & Metab, S-41345 Gothenburg, Sweden
[2] Sahlgrens Univ Hosp, Dept Internal Med, S-41345 Gothenburg, Sweden
[3] Sahlgrens Univ Hosp, Dept Physiol & Pharmacol, S-41345 Gothenburg, Sweden
[4] Univ Auckland, Res Ctr Dev Med & Biol, Auckland 1, New Zealand
关键词
D O I
10.1210/jc.83.8.2878
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
Several isoforms of human GH (hGH) are produced by two related genes expressed in the pituitary (hGH-N) and in the placenta (hGH-V). These genes consist of five exons (denoted 1-5) separated by four introns (denoted A-D). In the present report, two new transcripts of the hGH-V gene are described. The coding region of the hGH-V gene was amplified by RT-PCR using placental complementary DNA as template. DNA sequencing of several clones revealed two novel transcripts. One had a 45-bp deletion caused by the use of an alternative splice acceptor site within exon 3, similar to that in the hGH-N gene, predicting a 20-kDa isoform of hGH-V. The other transcript was generated by the use of an alternative splice donor site causing a 4-bp deletion in the end of exon 4, predicting a 24-kDa protein with 219 amino acids, which we refer to as hGH-V3. The carboxy-terminal sequence of hGH-V3 differs from 22-kDa hGH-V and hGH-V2, the two previously reported transcripts of the hGH-V gene, and does not contain a predicted transmembrane domain as described for hGH-V2. Ligase chain reaction was then used to analyze the possible use of the same splicing pattern in transcripts derived from the other genes of the hGH-gene cluster. Alternatively spliced transcripts encoding the 20-kDa hGH isoform were detected from the hGH-N and hGH-V genes, but not from the human chorionic somatomammotropin-A/B genes. The alternative splicing generating hGH-V3 was only demonstrated in transcripts derived from the hGH-V gene. Using competitive RT-PCR, the expression of hGH-V3 was estimated to be 10% of the hGH-V messenger RNA in full-term normal placentas and in placentas from pathological pregnancies. The 20-kDa hGH-V was detected in two of four full-term normal placentas, whereas a weak signal was observed in one of the pathological placentas. We conclude that the hGH-V primary transcript undergoes alternative splicing pathways generating at least four different messenger RNAs, predicting the expression of different hGH isoforms, including two with a complete sequence divergence in the carboxy-terminus.
引用
收藏
页码:2878 / 2885
页数:8
相关论文
共 42 条
[1]  
ANTHONY RV, 1995, J ANIM SCI, V73, P1861
[2]  
Barany F, 1991, PCR Methods Appl, V1, P5, DOI 10.1101/gr.1.1.5
[3]   THE HUMAN GROWTH-HORMONE GENE FAMILY - STRUCTURE AND EVOLUTION OF THE CHROMOSOMAL LOCUS [J].
BARSH, GS ;
SEEBURG, PH ;
GELINAS, RE .
NUCLEIC ACIDS RESEARCH, 1983, 11 (12) :3939-3958
[4]   GROWTH-HORMONE HETEROGENEITY - GENES, ISOHORMONES, VARIANTS, AND BINDING-PROTEINS [J].
BAUMANN, G .
ENDOCRINE REVIEWS, 1991, 12 (04) :424-449
[5]   SLOW METABOLIC-CLEARANCE RATE OF THE 20,000-DALTON VARIANT OF HUMAN GROWTH-HORMONE - IMPLICATIONS FOR BIOLOGICAL-ACTIVITY [J].
BAUMANN, G ;
STOLAR, MW ;
BUCHANAN, TA .
ENDOCRINOLOGY, 1985, 117 (04) :1309-1313
[6]   PLASMA TRANSPORT OF THE 20,000-DALTON VARIANT OF HUMAN GROWTH-HORMONE (20K) - EVIDENCE FOR A 20K-SPECIFIC BINDING-SITE [J].
BAUMANN, G ;
SHAW, MA .
JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM, 1990, 71 (05) :1339-1343
[7]   Metabolic actions of growth hormone: Direct and indirect [J].
Berneis, K ;
Keller, U .
BAILLIERES CLINICAL ENDOCRINOLOGY AND METABOLISM, 1996, 10 (03) :337-352
[8]   THE HUMAN GROWTH-HORMONE LOCUS - NUCLEOTIDE-SEQUENCE, BIOLOGY, AND EVOLUTION [J].
CHEN, EY ;
LIAO, YC ;
SMITH, DH ;
BARRERASALDANA, HA ;
GELINAS, RE ;
SEEBURG, PH .
GENOMICS, 1989, 4 (04) :479-497
[9]   SINGLE-STEP METHOD OF RNA ISOLATION BY ACID GUANIDINIUM THIOCYANATE PHENOL CHLOROFORM EXTRACTION [J].
CHOMCZYNSKI, P ;
SACCHI, N .
ANALYTICAL BIOCHEMISTRY, 1987, 162 (01) :156-159
[10]   A HOT-SPOT OF BINDING-ENERGY IN A HORMONE-RECEPTOR INTERFACE [J].
CLACKSON, T ;
WELLS, JA .
SCIENCE, 1995, 267 (5196) :383-386