Expression of messenger RNA for kit-ligand in human placenta: localization by in situ hybridization and identification of alternatively spliced variants.
Kit-ligand is a novel polypeptide growth factor which binds and activates the c-kit protooncogene, a receptor tyrosine kinase. We used the technique of reverse transcription-polymerase chain reaction to demonstrate the expression of this growth factor in human placenta. In situ hybridization showed that kit-ligand mRNA is expressed in cytotrophoblast and syncytiotrophoblast cells in the placenta, and in fetally derived extravillous trophoblast cells which have invaded the maternal endometrium. Five species of mRNA encoding variants of kit-ligand were identified by nested reverse transcription-polymerase chain reaction. Cloning and sequencing indicate that these variants arise by alternative splicing of the kit-ligand transcript. One of these species, KL486, uses a novel splice site in exon 8. There is a different pattern of expression of the variants in amnion, chorion, trophoblast, and placenta, indicating tissue-specific control of splicing.
Sharkey
A
A
Department of Obstetrics and Gynecology, University of Cambridge, Rosie Maternity Hospital, United Kingdom.
Jones
D S
DS
Brown
K D
KD
Smith
S K
SK
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D005260:Female; D016298:Hematopoietic Cell Growth Factors / Q000235:genetics*; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010920:Placenta / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis*; D019089:Stem Cell Factor
D016298:Hematopoietic Cell Growth Factors; D012333:RNA, Messenger; D019089:Stem Cell Factor