| Studies have shown that many Squamata reptiles scaly skin surface have skin sense receptors structure, which is similar to Phrynocephalus przewalskii. However, the study on molecular and histomorphology analyses about the skin sense receptors have lagged behind, and there are different views about the function of the skin receptors on different reptiles.We study the structure of the skin and skin sense receptors of Phrynocephalus przewalskii and the expression of SHH and EF-2 in the skin and skin sense receptors by in situ hybridization. The following results are concluded:(1) The epidermis consist of five layer, oberhautchen, beta-layer, mesos, alpha-layer, stratum basale. The integument of reptiles have developed to adapt to prevent water loss and protect from rigors of terrestrial life. (2) The skin sense receptors are cap-like protubulances residing in the scale pits, the surface of which takes on disk structure is covered with a long, thick sense hair. The skin sense receptor is heterogeneity on different part of the Phrynocephalus przewalskii, and there is only one sense receptor on one scale. Skin sense receptor has dual function of feeling mechanical stimulation and thermal radiation; (3) Through cloning and other methods, we cloned the P-keratin gene from the desert sand lizards back regenerated skin and analyzed the sequence, we found that the sequence has a high similarity with of eukaryotic elongation factor (EF-2); (4) EF-2 gene and the Shh gene are both expressed in the cells of skin epidermis and skin sense receptors, and also expressed in the pit bottom of the cap-like receptors, suggesting that the basal cells of the bottom and the cap-like protrusion parts can both proliferate, we presume that the desert sand lizard skin and skin receptors may have some similarity in the morphogenesis of the region, the hair may develop from the cell of the cap-like receptors. We study skin sense receptors to approach structure and function of skin sense receptors and homology of feathers and skin receptors of reptiles. |
