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Rehman, M.

Publications and source records attributed to Rehman, M..

6 recordsLinked to original sources

Anks3 mediates cilia dependent polycystin signaling and is essential for adult kidney homeostasis

The existence of a cilia-dependent cyst activation (CDCA) pathway underlying autosomal dominant polycystic kidney disease was identified by showing that cyst progression following loss of polycystins is significantly suppressed by removal of structurally intact cilia. We applied translating ribosome affinity purification RNASeq on pre-cystic mouse kidneys to determine a cell-autonomous in vivo translatome associated with CDCA and identified Glis2 as an early effector of polycystin signaling. Here, to discover additional components of CDCA, we used polycystin-dependent Glis2 expression as a functional readout and identified Anks3, from the CDCA pattern translatome, as a candidate cytosolic regulator of polycystin signaling. Anks3 regulates polycystin-dependent Glis2 expression both in vitro and in vivo. Anks3 also undergoes polycystin-dependent changes in phosphorylation state. Inactivation of Anks3 in Pkd1 mouse models suppresses cyst progression, but also results in rapidly progressive kidney injury independent of polycystins. Anks3 inactivation also normalizes a broader spectrum of polycystin-dependent CDCA translatome changes. These findings define Anks3 as a central regulator of cilia dependent polycystin signaling, functioning downstream of cilia and polycystins and upstream of Glis2, and show that Anks3 has broader functions in maintaining renal structural and functional homeostasis.

genetics↗

The AP2/ERF transcription factor HcERF5 confers drought tolerance via ABA-mediated signaling in kenaf

The APETALA2/ethylene response factor (AP2/ERFs) are pivotal in regulating abiotic stress responses in plants. However, the specific role of ERFs in kenafs response to drought stress remains unclear. In this study, a transcription factors HcERF5 was isolated from kenaf and its role in drought stress tolerance was analyzed. HcERF5 was found to localize in both nucleus and cytoplasm and could be significantly induced by polyethylene glycol-6000 (PEG-6000) and abscisic acid (ABA) in kenaf seedlings. In transgenic Arabidopsis expressing the HcERF5 promoter-driven {beta}-glucuronidase (GUS), strong GUS activity was observed in roots, stems, and leaves. Overexpression of HcERF5 in Arabidopsis enhanced seed germination rates under drought or ABA stress and improved drought tolerance in seedlings by increasing antioxidant enzyme activities, whereas aterf5 knockout lines exhibited the opposite trend. Additionally, HcERF5 overexpressing Arabidopsis showed significantly increased drought tolerance and reduced sensitivity to ABA. Furthermore, virus-induced gene silencing (VIGS) of HcERF5 in kenaf reduced drought tolerance, as evidenced by decreased antioxidant enzyme activity, increased stomatal aperture, and elevated levels of malondialdehyde (MDA), reactive oxygen species (ROS), and proline under drought stress. RNA-seq analysis further revealed that HcERF5 directly regulated ABA signaling pathway. Yeast-two-hybrid (Y2H) assays revealed 29 proteins that interact with HcERF5. Among them, the expression of downstream drought stress-related genes HcPRK, HcRD22, HcMAP2, HcCAB, HcCS, and HcCCoAOMT3 were significantly reduced in HcERF5-silenced plants. Overall, this study highlights the significant potential of HcERF5 in enhancing drought tolerance in kenaf. HighlightO_LIHcERF5 overexpression enhanced drought tolerance in kenaf, however silencing increased drought sensitivity. C_LIO_LIHcERF5 regulates ABA synthesis and increases kenaf stomatal conductance and density under drought stress. C_LIO_LIHcERF5 regulates plant hormone signal transduction, MAPK signalling, and phenylpropanoid biosynthesis in kenaf under drought stress. C_LIO_LIProtein interaction revealed HcERF5 interacts with six stress-response genes. C_LI

molecular biology↗

Pseudomonas aeruginosa impairs mitochondrial function and metabolism during infection of corneal epithelial cells

Pseudomonas aeruginosa (PA) is a gram-negative opportunistic pathogen that can infect the cornea as a result of trauma or contact lens wear. In addition to their known energy producing role, mitochondria are important mediators of immune signaling and host defense. While certain pathogens have developed strategies to evade host defenses by modulating host mitochondrial dynamics and metabolism, the ability of PA to harness host cell mitochondria during corneal infection is unknown. Using a combination of biochemical and imaging techniques, we show that PA infection of corneal epithelial cells induced mitochondrial fission in a DRP1-dependent manner that preceded PINK1/Parkin and FUNDC1-mediated mitophagy. PA also impaired NADH-linked respiration through a reduction in complex 1. This corresponded to a decrease in metabolic pathways related to glycolysis and the TCA cycle. Metabolomics analysis further demonstrated an upregulation of the pentose phosphate pathway, arginine, purine, and pyrimidine metabolism in PA infected cells. These pathways may provide a key source of nucleotides, amino acids, and nitrogen for both the host cell and PA, in addition to antioxidant functions. Following treatment with gentamicin to kill all extracellular bacteria, metabolic flux analysis showed that corneal epithelial cells were able to restore mitochondrial function despite the continued presence of intracellular PA. Taken together, these data demonstrate that mitochondrial dysfunction and metabolic rewiring in host cells is triggered by extracellular PA, but once inside, PA requires healthy mitochondria to ensure host cell survival.

microbiology↗

Transcriptomic analysis revealed reactive oxygen species scavenging mechanisms associated with ferrous iron toxicity in aromatic Keteki Joha rice

Lowland acidic soils with water-logged regions are often affected by ferrous iron (Fe2+) toxicity, a major yield-limiting factor of rice production. The Reactive Oxygen Species (ROS) was hypothesized to be crucial under severe Fe2+ toxicity conditions. However, molecular mechanisms and associated ROS homeostasis genes are still not well-explored. In this study, a comparative RNA-Seq based transcriptome analysis was conducted to understand the Fe2+ toxicity tolerance mechanism in aromatic Keteki Joha. About 69 Fe homeostasis related genes and their homologs were identified, where most of the genes were downregulated. Differentially expressed genes (DEGs) are associated with biological processes-response to stress, stimulus and abiotic stimulus. DEGs involved in the Biosynthesis of amino acids, RNA degradation, Glutathione metabolism etc. were induced, whereas, Phenylpropanoid biosynthesis, Photosynthesis, and Fatty acid elongation were inhibited. The Mitochondrial iron transporter (OsMIT), Vacuolar Iron Transporter 2 (OsVIT2), Ferritin (OsFER), Vacuolar Mugineic Acid Transporter (OsVMT), Phenolic Efflux Zero1 (OsPEZ1), Root Meander Curling (OsRMC), Nicotianamine synthase (OsNAS3), etc. were upregulated in different tissues suggesting the importance of Fe retention and sequestration for detoxification. However, several antioxidants, ROS scavenging genes and abiotic stress-responsive transcription factors indicate ROS homeostasis as one of the most important defense mechanisms under severe Fe2+ toxicity. The CAT, GSH, APX, MDHAR, DHAR, GR were upregulated. Moreover, abiotic stress-responsive transcription factors NAC, MYB, ARF, bZIP, WRKY, C2H2-ZFP were also upregulated. Accordingly, ROS homeostasis has been proposed to be an important defense mechanism under such conditions. Thus, our results will enrich the knowledge of understanding Fe-homeostasis in rice.

genomics↗

A polyphenol-rich extract of Olive Mill Wastewater Enhances cancer chemotherapy effects while mitigating cardiac toxicity.

BackgroundCardiovascular toxicities still remain one of the most undesirable side effects in cancer patients receiving chemotherapy, and cardiotoxicity has been detected associated with many therapeutic regimens. A number of mechanisms are reported for these effects, some of which are related to inflammation, oxygen radical generation, mitochondrial damage. Extra-virgin olive oil (EVOO) is rich in cancer preventive polyphenols endowed with anti-inflammatory, antioxidant activities which could exert protective effects on the heart cells. One very interesting derivative of EVOO preparation is represented by purified extract form waste waters. Here, we investigated the anti-cancer activity when combined with chemotherapeutics as well as potential cardioprotective activities of a polyphenol-rich extract from waste product of the EVOO, named A009. Methods and ResultsMice bearing prostate cancer (PCa) xenografts were treated with cisplatin with and without A009. Tumor cell growth was reduced by cis and by A009 and further hindered by the combination. The effects of the A009 extract on cardiovascular toxicities was investigated in vivo. Hearts of mice were analyzed, and the mitochondria were studied by transmission electron microscopy. A protection activity by A009 was observed. To confirm the in vivo data obtained with cisplatin therapy, tumor cell lines and rat cardiomyocytes were treated with cisplatin in vitro with and without A009. A009 enhanced cisplatin and 5FU reduced cancer cell growth while did not further affect co-treated rat cardiomyocytes. Another frequently used chemotherapeutic agent 5-fluorouracil (5FU), was also tested in this assay a similar effects were observed. The cardioprotective effects of the A009 extract towards 5 FU chemotherapy were further investigated in a second system of in vitro cultures, on cardiomyocytes freshly isolated from mice pups. These cells were treated with 5-fluorouracil and A009. Wastewater extract mitigated toxicity of the fluorpyrimidine. ConclusionsIn vivo, we found synergisms of A009 and cisplatin in prostate cancer treatment. Hearts of mice xenografted with PCa cell lines and receiving co-treatments of A009 extracts along with cisplatin had reduced mitochondria damage compared to chemotherapy alone, indicating a cardioprotective role. A009 in vitro was additive to cisplatin and 5FU to reduce cancer cell growth while did not further affect rat cardiomyocytes cell cultures treated with cisplatin and 5FU. The A009 extract also rescued the proliferation rate of neonatal murine cardiomyocytes treated with 5-Fluorouracil. Our study demonstrates that the polyphenol rich purified A009 extracts enhances the effect of chemotherapy in vitro and in vivo but mitigates effects on heart and heart cells. It could therefore represent a potential candidate for cardiovascular prevention in patients undergoing cancer chemotherapy.

cancer biology↗

Forensic features and genetic legacy of the Baloch population of Pakistan and the Hazara population across Durand-line revealed by Y chromosomal STRs

Hazara population across Durand-line has experienced extensive interaction with Central Asian and East Asian populations. Hazara individuals have typical Mongolian facial appearances and they called themselves descendants of Genghis Khans army. The people who speak the Balochi language are called Baloch. Previously, a worldwide analysis of Y-chromosomal haplotype diversity for rapidly mutating (RM) Y-STRs and with PowerPlex Y23 System (Promega Corporation Madison, USA) kit was created with collaborative efforts, but Baloch and Hazara population from Pakistan and Hazara population from Afghanistan were missing. A limited data with limited number of markers and samples is available which poorly define these populations. So, in the current study, Yfiler Plus PCR Amplification Kit loci were examined in 260 unrelated Hazara individuals from Afghanistan, 153 Hazara individuals, and 111 Balochi individuals from Baluchistan Pakistan. For the Hazara population from Afghanistan and Pakistan overall, 380 different haplotypes were observed on these 27 Y-STR loci, gene diversities ranged from 0.51288 (DYS389I) to 0.9257 (DYF387S1) and haplotype diversity was 0.9992 +/- 0.0004. For the Baloch population, every individual was unique at 27 Y-STR loci, gene diversity ranged from 0.5718 (DYS460) to 0.9371(DYF387S1). Twelve haplotypes shared between 178 individuals while only two haplotypes among these twelve were shared between 87 individuals in Hazara populations. Rst and Fst pairwise genetic distance analyses, multidimensional scaling (MDS) plot, Neighbor-joining (NJ) tree, linear discriminatory analysis (LDA), and median-joining network (MJNs) were performed, which shed light on the history of Hazara and Baloch populations. Interestingly null alleles were observed at DYS448 with specific mutation patterns in Hazara populations. The results of our study showed that the Yfiler Plus PCR Amplification Kit marker set provided substantially stronger discriminatory power in the Baloch population of Pakistan and the Hazara population across the Durand-line.

evolutionary biology↗