Abstract
PTHrP is found in a wide variely of tissues. The structure of the human PTHrP gene is complex and alternative splicing allows expression of three different isoforms {PTHrP139 PTHrP141 and PTHrP173). In other species fewer isoforms are expressed. To find out which of the isoforms that are expressed in human mammary gland epithelial cells a RT-PCR method was developed distinguishing the three variants. mRNA isolated from human hreast milk cells, human mammary epithelial cells (HMF,C) and human non-lactating mammary gland cells were analyzed. The RT-PCR experiments resulted in amplification of DNA fragments corresponding to all three isoforms for the three cell tjpes tested. The nucleotide sequences of the PCR fragments was verified to he identical to the reported sequences. 'I he biological significance of the three isoforms is so far unknown. However, several biological functions have been ascribed to PTHrP, e.g. calcium regulation, smooth muscle relaxation, regulation of cellular growth and differentiation. The conspicuously high level of PTHrP in human milk taken together with immature gastrointestinal functions in the newborn make it tempting to speculate that milk PTHrP has a physiological function in the recipient infant.
| Original language | English |
|---|---|
| Title of host publication | FASEB Journal|FASEB J. |
| Place of Publication | Cambridge, UK |
| Publisher | Cambridge University Press |
| Pages | A749 |
| Volume | 10 |
| Publication status | Published - 1996 |