Objective - Platelet-derived growth factor (PDGF) is involved in the control of cell proliferation, differentiation and survival in various tissues of vertebrates. However, little is known about the expression of PDGF in the developing cochlea of rodents. Material and Methods - We examined the expression of PDGF family genes in the developing cochlear tissue of rats using microarrays and tested their role in the proliferation of progenitor hair cells using cellular and molecular biology techniques. Results - It was found that the genes for PDGF-A, PDGF receptor (R)-α and PDGFR-β were highly expressed in the rapidly growing otocyst on embryonic Days 12-14 and weakly expressed thereafter. Reverse transcriptase polymerase chain reaction demonstrated the expression of PDGF-C and confirmed the expression of PDGF-A and PDGFR-α and -β in the developing cochlear tissue of rats and the cultured progenitor hair cells. Inhibition of the expression of PDGFs in the cultured progenitor hair cells with antisense oligonucleotides reduced the DNA synthesis. Conclusion - PDGFs and their receptors may play a role in the proliferation of developing cochlear hair cells.
Bibliographical noteFunding Information:
The authors thank Mrs Yunjun Lee for technical assistance and Eileen P. Schlentz for editorial assistance in the preparation of the manuscript. This work was supported by National Institutes of Health grants Nos. R01 DC03433 and P30 DC04660 from the National Institute of Deafness and Other Communication Disorders, the Multiple District (5M) Lion’s Hearing Foundation and the National Organization for Hearing Research.
- Otocyst development
- Platelet-derived growth factor
- Proliferation of progenitor hair cells