The baboon expresses the calbindin-D9k gene in intestine but not in uterus and placenta: Implication for conservation of the gene in primates

✍ Scribed by Eui-Bae Jeung; Nancy C. Fan; Peter C. K. Leung; John C. Herr; Alex Freemerman; Dr. John Krisinger

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 753 KB
• Volume: 40
• Category: Article
• ISSN: 1040-452X
• DOI: 10.1002/mrd.1080400403

✦ Synopsis

Expression of the Calbindin-D9k (CaBP-9k) gene was studied in the baboon. Northern blot analysis using a human CaBP-9k cDNA probe detected expression in duodenum but not in uterus and placenta. Reverse transcription/polymerase chain reaction (RT/PCR) confirmed this expression pattern and indicated a high degree of identity between the baboon and human CaBP-9k mRNAs. PCR was employed to amplify the intron A region of the baboon CaBP-9k gene using human-derived primers and baboon genomic DNA. The baboon intron was closely related to the human CaBP-9k intron A, including the presence a complete Alu-repetitive element. Most significantly, a 13 nucleotide long element at the 5' end of the baboon intron matched exactly the human sequence. This element represents a nonfunctional variation of an estrogen response element found at the same location in the rat CaBP-9k gene. The rat element functions as an enhancer and mediates uterine and possibly placental CaBP-9k expression in the rat and probably most other mammals. The finding of a modified ERE in baboon as in human suggests that during primate evolution the expression of this mammalian-specific gene has been eliminated in uterus and placenta. This scenario raises the question of the role of CaBP-9k in these reproductive tissues.