LIM homeodomain proteins Islet-1 and Lim-3 expressions in the developing pineal gland of chick embryo by immunohistochemistry
Article first published online: 7 JUL 2006
Journal of Pineal Research
Volume 41, Issue 3, pages 247–254, October 2006
How to Cite
Zhang, J.-H., Liu, J.-L., Wu, Y.-J. and Cui, S. (2006), LIM homeodomain proteins Islet-1 and Lim-3 expressions in the developing pineal gland of chick embryo by immunohistochemistry. Journal of Pineal Research, 41: 247–254. doi: 10.1111/j.1600-079X.2006.00363.x
- Issue published online: 7 JUL 2006
- Article first published online: 7 JUL 2006
- Received May 22, 2006; accepted May 31, 2006.
- chick embryo;
- pineal gland
Abstract: LIM homeodomain proteins Islet-1 and Lim-3 expression and their role in nervous tissue and endocrine glands have been reported; however, nothing is known concerning Islet-1 and Lim-3 expression in the developing pineal gland of the chick embryo. The aim of the present study was to determine the ontogeny of Islet-1 and Lim-3 expression in the developing pineal gland of chick embryo using immunohistochemistry. The results showed that Islet-1 and Lim-3 immunopositive cells were first detected in the pineal evagination of chick embryos at day 4 (E4) and E4.5 of incubation, respectively. In the later developing stages, both Islet-1 and Lim-3 immunopositive cells were consistently detected in the follicular and parafollicular pinealocytes throughout the pineal gland. The relative percentage of Islet-1 immunopositive (Islet-1+) cells relative to the total cells was about 6% at E4.5, and then kept increasing (P < 0.05) and reached about 40% by E12.5; this was followed by no obvious changes until the chicks were newly hatched. The change in Lim-3 immunopositive (Lim-3+) cell number was parallel to that of Islet-1, although Lim-3+ cell were significantly fewer than Islet-1+ cell numbers from E4.5 to E8.5 (P < 0.05). Dual immunohistochemical staining results showed that almost all the Lim-3+cells expressed Islet-1 at every stage examined, and about 90% of Islet-1+cells were proliferating cell nuclear antigen negative. These results suggest that both Islet-1 and Lim-3 may be involved in regulating the development and functional maturation of the pineal gland, although further studies are required in elucidating the functional roles of Islet-1 and Lim-3 and the related mechanisms.