Exon/intron organisation of human proteasome PROS-27 K gene

The potential role of PSMA6 in modulating fat deposition in pigs by promoting preadipocyte proliferation and differentiation

To investigate whether the proteasome subunit alpha 6 (PSMA6) gene has an effect on fat deposition, the gene expression profile was first detected in Berkshire pigs and Jinhua pigs (JHP). The results demonstrated that significantly higher levels of mRNA expression were identified in adipose tissues and the liver. Interestingly, when compared to the longissimus dorsi muscle (LDM) in each breed, it was discovered that the expression levels of the PSMA6 gene in these tissues of JHP were considerably higher than those in Berkshire pigs. Meantime, some significant correlations of PSMA6 mRNA expression in lipid metabolism-related tissues such as the liver and LDM with the marbling score, as well as the content of intramuscular fat (IMF), in pigs were found by correlation coefficient analysis. To further explore the effects of PSMA6 expression on fat deposition, we performed PSMA6 overexpression in 3T3-L1 cells via Lentivirus infection. Our results indicated that PSMA6 could promote cell proliferation and accelerate cell division. It was also found that the transcription factors CCAAT/enhancer-binding protein alpha (CEBPA) and peroxisome proliferator-activated receptor gamma (PPARG), as well as the key genes related to adipogenesis, were upregulated, while the genes related to fat oxidation were significantly downregulated, which indicated that the PSMA6 gene could stimulate the differentiation of preadipocytes.

Association between functional variant of inflammatory system gene (PSMA6) and end-stage kidney disease

Background

The proteasome system is involved in several disorders. The 5′ untranslated region of PSMA6 gene contains a single nucleotide polymorphism (SNP) −8 C/G, associated with diabetes, myocardial infarction and coronary artery disease.

Methods

We examined 584 patients with end-stage kidney disease (ESKD) and 430 controls. All were genotyped for −8 C/G SNP by polymerase chain reaction and restriction analysis.

Results

We observed lower frequency of CG + GG genotypes in patients than in controls (20 vs. 42 %, p = 0.0038). The odds ratio of 0.34 (95 % CI 0.26–0.45) suggests association of CG + GG with decreased risk of ESKD. We investigated the association between PSMA6 polymorphism and LVH present in 54 % of patients. There was a significant association of CG + GG genotype with LVH, with over 75 % of CG + GG in patients with LVH. This effect was independent from other common causes of LVH—age (OR 1.12, p = 0.643) and hypertension (OR 1.72, p = 0.422).

Conclusion

We demonstrated for the first time that PSMA6 polymorphism might be a protective factor for ESKD. On the other hand, CG + GG genotypes are independently related to LVH in ESKD patients.

Validation of the association between PSMA6 -8 C/G polymorphism and type 2 diabetes mellitus in Chinese Dongxiang and Han populations

OBJECTIVE

The aim of our study was to validate association between -8 C/G variant of PSMA6 gene and T2DM in Chinese Dongxiang and Han populations.

METHOD

We genotyped PSMA6 gene -8 C/G polymorphism in the control groups and T2DM groups in two populations from China using PCR-RFLP technique. Phenotypes and biochemical indicators were measured by biochemical technique.

RESULT

The frequencies of CG+GG genotype were observably different from CC genotype in the T2DM groups and control groups (for Dongxiang population: OR = 1.341, 95% CI: 1.101-1.632, P = 0.004; for Han population: OR = 1.313, 95% CI: 1.085-1.569, P = 0.006 after adjusting for gender, age, and BMI, respectively). In the Dongxiang population, the FPG, HOMA-IR, SBP and TG levels of CG+GG genotype were markedly higher than those of the CC genotype in control group (all P < 0.05). However, in the Han population, we only found that the FPI level of the CC genotype was significantly higher than that of the CG+GG genotype in control group (P < 0.05).

CONCLUSION

Our investigation suggests that -8 C/G variant of PSMA6 gene may be associated with T2DM and diabetes-related metabolic traits in Chinese Dongxiang and Han populations.