---

Objective: Considering the importance of integrin molecules in the implantation and lack of sufficient information in the expression pattern of these molecules in various phases of estrous cycle. It seemed to be necessary to investigate these molecules in mouse endometrial during the various phases of oestrous cycle. Materials and Methods: Female NMRI mice (n=15) aged 6-8 weeks were studied. Various phases of estrous cycle including: proestrus, estrus, metestrus and diestrus were determined by vaginal smear. The mice were sacrificed (at least 3 per each phase) by cervical dislocation and the tissues were obtained from the middle 1/3 part of their uterine horns at each phase then the cryosections at thicknesses between 8-10 μ were obtained. Then the immunohistochemistry were done for integrins of 4, 1, v, 3 and their ligand osteopontine. Results: The integrins were expressed only in the metestrous phase of oestrous cycle in the different locations of mouse endometrium. The positive reactions were observed for αv, α4 and β3 in the apical and basal membrane of glandular epithelium. Also the positive reaction for β1 was found in surface and glandular epithelium as well as stroma. The osteopontin expression was seen in the apical membranes of surface and glandular epithelium and was not seen in other locations. Conclousion: It seems that expression of integrins in endometrium is based on their role in the implantation, therefore the molecules α4, β1 and OPN that are expressed on the surface epithelial may be involve in the adhesion of cell to cell and integrins of αv, β3 that are expressed in the glandular

---

MicroRNAs are endogenous noncoding RNA that play vital roles in all plant cellular metabolic processes by mediating target gene expression. To date, miRNAs in Taraxacum spp., which is an important industrial plant, have remained largely unknown. In the present study, 970 miRNAs from 399 families were identified in Taraxacum spp by conducting computational approaches. The most frequent miRNAs in Taraxacum spp was miR5021. According to the KEGG results, miR5021, miR838, and miR1533 are related to the terpene biosynthesis pathway, while miR5015b, and miR1436 are involved in the starch and sucrose biosynthesis pathways. Quantitative real-time PCR assay was performed to validate the expression levels of five predicted miRNAs and 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase (HMGCR) and invertase as the target genes. Results indicated that the highest relative expression of miR1533 and miR1436 occurred in the flower, while the highest transcripts levels of miR5015b were observed in the stem. In addition, the higher relative expression level of the miR5021 and miR838 was consistent with the lower expression level of the HMGCR gene in all tissue, suggesting that miR5021 and miR838 are involved in regulating HMGCR gene expression. Since mevalonate pathway is the main source of isopentenyl pyrophosphate, which is used in the synthesis of rubber, miR5021 and miR838 play an important role in the production of rubber by regulating the expression of HMGCR enzyme. These findings will accelerate future perspective studies on the regulatory mechanisms of miRNAs in Taraxacum kok-saghyz.