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In the present study, mitochondrial DNA polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to assess the population structure and genetic relationships among six Persian sturgeon, Acipenser persicus populations from the south Caspian Sea along the Iranian coast. The complete nucleotide dehydrogenase subunit 5 (NADH 5) region of mtDNA amplified by PCR was digested with five restriction enzymes. In total, 154 individuals from six populations including: Guilan (Zone1-2), Mazandaran (Zone 3 and 5), Golestan (Zone 4) and Sefidroud River, from the south Caspian Sea along the Iranian coast were analyzed using five restriction endonucleases (Rsa І, Hinf І, HaeIII, Mbo І and Cfr13І), yielding 17 haplotypes. Samples from Sefidroud River were clearly identified by cluster and molecular variance model (AMOVA) analyses. This collection showed dominant haplotypes that were little in populations from the other geographic areas. The mean haplotype diversity (h) and nucleotide diversity (π) were 0.739±0.038 and 0.0105±0.0043, respectively. Based on heterogeneity test haplotype frequencies of Persian sturgeon populations and Monte-Carlo with 1000 replicates in PCR-RFLP method significant differences were seen (χ2 =37.12, P< 0.0001) and these results showed that haplotype distribution in different location were significant and populations of Sefidroud River were statistically significant (P< 0.0001). This result suggests that the unique genetic structure of Sefidroud River represents a highly valuable genetic resource and should now be treated as demographically independent and managed separately.

The Persian sturgeon, Acipenser persicus (Borodin, 1897), is an economically important species, which mainly inhabits the Caspian Sea. However, little is known about its population genetic structure. In this study, variation in nucleotide sequences of the mitochondrial DNA (mtDNA) control region of wild stock Persian sturgeon was determined to assess the genetic diversity among different natural populations of this species. The fish (n = 46) were collected from four sites (Astara, Sefidrood, Noshahr and BandareTurkaman) in the south Caspian Sea. As a result 6 haplotypes and 44 variable sites were found. The average haplotype diversity (h) and nucleotide diversity (π) were 0.640±0.028 and 0.0442±0.011, respectively. Analysis of molecular variance (AMOVA) demonstrated that most variations occurred within samples, and the difference between the populations from Astara and Noshahr or Bandare- Turkaman was not significant (p

The brain 3β-hydroxysteroid dehydrogenase (3β-HSD), is the enzyme that catalyzes the biosynthesis of a neuroprotective factor, progesterone. The regulation of 3β-HSD in response to stress exposure in the cuprizone-induced model of Multiple Sclerosis was investigated and the reaction related to the demyelination extremity. 32 female Wistar rats divided into four groups (i.e., control group (Cont), non-stress cuprizone treated (N-CPZ), physical stress- cuprizone treated (P-CPZ) and emotional stress- cuprizone treated (E-CPZ). A witness foot-shock model used to induce background stress for 5 days. An elevated-plus maze applied to validate the stress induction. Followed by 6 weeks of cuprizone treatment, the Y-maze test performed to confirm brain demyelination. 3β-HSD gene expression as an indicator of progesterone synthesis examined. At the behavioral level, both stressed groups reflected more impaired spatial memory compared to the N-CPZ group (p < 0.01), with more severe results in the E-CPZ group (p < 0.01). The results of mRNA expression of 3β-HSD illustrated significant elevation in all cuprizone treated groups (p < 0.001) with a higher up-regulation (p < 0.001) in the E-CPZ group. Background stress -particularly emotional type- exacerbates the demyelination caused by cuprizone treatment. The brain up-regulates the 3β-HSD gene expression as a protective response relative to the myelin degradation extent., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

PRPF31 is ubiquitously expressed splicing factor and has an essential role in the pre-mRNA splicing in all tissues. However, it is not clear how reduced expression of this general splicing factor leads to retinal restricted disease, retinitis pigmentosa (RP). In this study, we used RNA interference and RNA-sequencing to mimic the PRPF31 haploinsufficiency in human organotypic retinal cultures (HORCs). We examined the effects of PRPF31 deficiency on splicing by analyzing the differential exon usages (DEUs) and intron retentions of the retinal transcriptome. Our results revealed that the PRPF31 deficiency causes mis-splicing of genes involved in RNA processing (PRPF3, PRPF8, PRPF4, and PRPF19) and phototransduction (RHO, ROM1, FSCN2, GNAT2, and GNAT1) in the retina in the PRPF31 reduced samples. Mis-splicing of genes implicated in phototransduction was associated with photoreceptor degeneration observed in RP patients. Our data revealed that PRPF31 deficiency leads to the mis-splicing of a distinct subset of pre-mRNAs with a widespread effect on phototransduction and RNA processing.

The splicing factor PRPF31 is the most commonly mutated general splicing factor in the retinitis pigmentosa. We used a rapid, convenient and cost effective transfection method with an efficient PRPF31 knockdown in HORFC in order to study the effect of PRPF31 downregulation on retinal gene expressions in an ex vivo model. Modified calcium phosphate method was used to transfect HORFC by PRPF31 siRNA. Different times and doses of siRNA for transfection were assayed and optimum condition was obtained. PRPF31 mRNA and protein downregulation were assessed by qRTPCR and Western blot. The tissue viability of HORFC was measured using the MTT. ImageJ analysis on stained retinal sections by immunohistochemistry was used for thickness measurement of outer nuclear photoreceptor layer. The PRPF31 gene downregulation effects on retinal specific gene expression were analyzed by qRTPCR. A total of 50 nM of PRPF31 siRNA transfection after 63 h in HORFC, showed the optimum reduction in the level of PRPF31 mRNA and protein as shown by qRTPCR and Western blot (over 90% and 50% respectively). The PRPF31 mRNA silencing with calcium phosphate had no effect on cell viability in the period of the experiment. Thickness measurement of outer nuclear photoreceptor layer with IHC showed the significant reduction after 63 h of study (P value = 0.02). siRNA induced PRPF31 knockdown, led to reduction of retinal specific mRNA gene expression involved in phototransduction (RHO, GNAT1, RP1), photoreceptor structure (ROM1, FSCN2, CA4, SEMA4) and transcription factor (CRX) (fold change >5), after 63 h., (© 2018 Wiley Periodicals, Inc.)