Publications by authors named "Samirul Bashir"

The Endoplasmic Reticulum is a pervasive, dynamic cellular organelle that performs a wide range of functions in the eukaryotic cell, including protein folding and maturation. Upon stress, ER activates an adaptive cellular pathway, namely Unfolded Protein Response, that transduces information from ER to nucleus, restoring homeostasis in the ER milieu. UPR consists of three membrane-tethered sensors; IRE1, PERK and ATF6.

View Article and Find Full Text PDF

Alzheimer's disease (AD) is the most common form of dementia, generally affecting elderly people in the age group of above 60-65 years. Amyloid deposition has been found to be a possible cause and a characteristic feature of Alzheimer's disease. Mutations, variant genotypes, or downregulation that reduce amyloid clearance or accelerate amyloid accumulation can lead to Alzheimer's disease.

View Article and Find Full Text PDF

IRE1 belongs to a type I transmembrane protein family harboring two functional domains, cytoplasmic domain with kinase and RNAse catalytic activity, and the luminal domain, which is involved in the sensing of unfolded proteins. IRE1 molecule undergoes dimerization in the lumenal domain, which functionally activates the catalytic C-terminal domain. IRE1 activation is directly related to transition between monomeric and dimeric forms.

View Article and Find Full Text PDF

IRE1 is a transmembrane signalling protein that activates the unfolded protein response under endoplasmic reticulum stress. IRE1 is endowed with kinase and endoribonuclease activities. The ribonuclease activity of IRE1 can switch substrate specificities to carry out atypical splicing of Xbp1 mRNA or trigger the degradation of specific mRNAs.

View Article and Find Full Text PDF

The endoplasmic reticulum is primarily responsible for protein folding and maturation. However, the organelle is subject to varied stress conditions from time to time, which lead to the activation of a signaling program known as the Unfolded Protein Response (UPR) pathway. This pathway, upon sensing any disturbance in the protein-folding milieu sends signals to the nucleus and cytoplasm in order to restore homeostasis.

View Article and Find Full Text PDF

Alpha1-antitrypsin (α1AT) is an abundant serine-protease inhibitor in circulation. It has an important role in neutralizing the neutrophil elastase activity. Different pathogenic point mutations like Z-α1AT have been implicated in the development of liver cirrhosis and Chronic Obstructive Pulmonary Disease (COPD), the latter being a cluster of progressive lung diseases including chronic bronchitis and emphysema.

View Article and Find Full Text PDF

Wall ex. Benth. (Lamiaceae) has been reported to possess many biological activities including antibacterial, antifungal, antispasmodic and antioxidant activity but there is no report as such on its mutagenic and/or anti-mutagenic activity.

View Article and Find Full Text PDF

Purpose: Different mutations in coding and non-coding sequences of the SERPINA1 gene have been implicated in the pathogenesis of COPD. However, - 10T/C mutation in the hepatocyte-directed promoter region has not been associated with COPD pathogenesis so far. Here, we report an increased frequency of - 10C genotype that is associated with decreased levels of serum alpha1-antitrypsin (α1AT) in COPD patients.

View Article and Find Full Text PDF

Alpha-1-antitrypsin (AAT) is an acute phase secretory glycoprotein that inhibits neutrophil proteases like elastase and is considered as the archetype of a family of structurally related serine-protease inhibitors termed serpins. Serum AAT predominantly originates from liver and increases three to five fold during host response to tissue injury and inflammation. The AAT deficiency is unique among the protein-misfolding diseases in that it causes target organ injury by both loss-of-function and gain-of-toxic function mechanisms.

View Article and Find Full Text PDF

Alpha1-antitrypsin (AAT) is one of the major circulating anti-protease whose levels in circulation are raised during excessive amount of proteases, especially neutrophil elastase (NE) released during the course of inflammation. Proteolytic attack of NE on peripheral organs, more exclusively on lung parenchyma has severe consequence that may precipitate pulmonary emphysema. Normally, human body has its own molecular and physiological mechanisms to synthesize and regulate the production of anti-protease like AAT to mitigate the extent of inflammatory damage.

View Article and Find Full Text PDF

Aims: Osmolytes are small organic molecules which play a significant role in maintaining functional homeostasis of proteins under extreme hostile stresses. Any imbalance to cell homeostasis leads to Endoplasmic Reticulum stress (ER-stress) to which a set of cellular responses both at transcriptional and translational level are initialed for restoration of cellular homeostasis called Unfolded Protein Response (UPR). In the present study we evaluated the role of Sarcosine, Betaine, Hydroxyectoine and Ectoine as potential modulators of UPR.

View Article and Find Full Text PDF

The multiple short introns in Schizosaccharomyces pombe genes with degenerate cis sequences and atypically positioned polypyrimidine tracts make an interesting model to investigate canonical and alternative roles for conserved splicing factors. Here we report functions and interactions of the S. pombe slu7(+) (spslu7(+)) gene product, known from Saccharomyces cerevisiae and human in vitro reactions to assemble into spliceosomes after the first catalytic reaction and to dictate 3' splice site choice during the second reaction.

View Article and Find Full Text PDF

The yeast Bud31 protein, a Prp19 complex (NTC) member, aids spliceosome assembly and thus promotes efficient pre-mRNA splicing. The bud31 null cells show mild budding abnormalities at optimal growth temperatures and, at higher temperatures, have growth defects with aberrant budding. Here we have assessed cell cycle transitions which require Bud31.

View Article and Find Full Text PDF