Genetic Analysis of the Hsm3 Protein Function in Yeast Saccharomyces cerevisiae NuB4 Complex

In the nuclear compartment of yeast, NuB4 core complex consists of three proteins, Hat1, Hat2, and Hif1, and interacts with a number of other factors. In particular, it was shown that NuB4 complex physically interacts with Hsm3p. Early we demonstrated that the gene HSM3 participates in the control of replicative and reparative spontaneous mutagenesis, and that hsm3Δ mutants increase the frequency of mutations induced by different mutagens. It was previously believed that the HSM3 gene controlled only some minor repair processes in the cell, but later it was suggested that it had a chaperone function with its participation in proteasome assembly. In this work, we analyzed the properties of three hsm3Δ, hif1Δ, and hat1Δ mutants. The results obtained showed that the Hsm3 protein may be a functional subunit of NuB4 complex. It has been shown that hsm3- and hif1-dependent UV-induced mutagenesis is completely suppressed by inactivation of the Polη polymerase. We showed a significant role of Polη for hsm3-dependent mutagenesis at non-bipyrimidine sites (NBP sites). The efficiency of expression of RNR (RiboNucleotid Reducase) genes after UV irradiation in hsm3Δ and hif1Δ mutants was several times lower than in wild-type cells. Thus, we have presented evidence that significant increase in the dNTP levels suppress hsm3- and hif1-dependent mutagenesis and Polη is responsible for hsm3- and hif1-dependent mutagenesis.

Effects of resveratrol on VEGF & HIF1 genes expression in granulosa cells in the angiogenesis pathway and laboratory parameters of polycystic ovary syndrome: a triple-blind randomized clinical trial

OBJECTIVES

Management options for PCOS, as the most prevalent endocrine disorder in women of reproductive age, using natural supplements have a high priority for physicians, especially based on the etiological pathways. Therefore, this study was conducted to describe the effect of resveratrol on the angiogenesis pathway, for management of PCOS through assessing VEGF, HIF1 gene expression, and laboratory parameters.

METHODS

In this triple-blind RCT, PCOS was confirmed in ICSI candidates based on the Rotterdam criteria. Sixty-two patients that met the inclusion criteria were randomly assigned to two groups. All patients took resveratrol 800 mg/day or placebo for 40 days orally from the beginning of their previous menstruation cycle until the oocyte retrieval day. The serum levels of different hormones were measured, and the expression of HIF1 & VEGF genes was quantified by real-time PCR.

RESULTS

As for the laboratory hormone assay in 61 PCOS patients, a significant mean difference was seen in the FSH, LH, TSH, and testosterone between the two groups (P < 0.05). The results showed a reduction in the expression of VEGF & HIF1 genes under the effect of resveratrol in the granulosa cells (P = 0.0001). The number of mature oocytes, cleavage rate, fertilization rate, and fertility rate were not significantly different between the two groups (P > 0.05), but the high-quality oocyte rate and high-quality embryo rate were higher in the resveratrol group (P < 0.05).

CONCLUSIONS

Based on the results, resveratrol may improve some outcomes of PCOS patients, probably through changing the serum levels of some sex hormones and expression of VEGF & HIF1 genes in the angiogenesis pathway of granulosa cells.