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Objective: To predict the tertiary structure of human interferon alpha/beta receptor 2 protein. Study Design: Structure prediction by using bio informatics tools. Place and Duration of Study: Department of Biochemistry, Swat Medical College (STMC), Saidu Shareef, Swat, Pakistan, from Aug 2019 to Dec 2019. Methodology: All protein sequences of human interferon alpha/beta receptor 2 (isoforma, b and c) (IFNAR-2) were retrieved through the BLAST search (The Basic Local Alignment Search Tool) from available databases ‘NCBI’ (National Centre for Biotechnology Information) and ‘Uni Prot KB’ (The Universal Protein Resource). Sequence alignment was conducted by using Clustal Omega, to get the consensus sequence for IFNAR-2 protein. Consensus protein sequence of human IFNAR-2 was used for the prediction of the three-dimensional structure by employing Swiss-Model Server. Moreover, subcellular localization analysis was also performed by using CELLO2GO program. Results: Structural model of human IFNAR-2 protein was predicted and evaluated by Ramachandran dimension. Cellular localization of tertiary topological domains of the predicted models were revealed probability of localization of IFNAR-2 protein (isoform a, b & c) is highest in the plasma membrane due to the presence of the transmembrane alpha helical regions. Conclusion: This study predicted the tertiary structural dimensions of human IFNAR-2 protein, including the specific topological domains that contribute towards the subcellular compartmentalization and functional characteristics. [ABSTRACT FROM AUTHOR]

Introduction: Mucopolysaccharidosis type II (MPS-II) or Hunter syndrome is a rare X-linked recessive disorder caused by genetic lesions in the IDS gene, encoding the iduronate-2-sulfatase (IDS) enzyme, disrupting the metabolism of certain sulfate components of the extracellular matrix. Thus, the undegraded components, also known as glycosaminoglycans, accumulate in multiple tissues resulting in multisystemic abnormalities. Objective: To uncover causative genetic lesions in probands of three unrelated Pakistani families affected with rare X-linked recessive Hunter syndrome. Methods: Screening of the IDS gene was performed in six individuals (three patients and their mothers) through whole genomic DNA extraction from peripheral blood followed by PCR and Sanger sequencing. MutationTaster, PROVEAN, Human Splicing Finder, Swiss-Model, and SwissPdbViewer were used for in silico analysis of identified variants. Results: All probands were presented with coarse facies, recurrent respiratory tract infection, and reduced IDS activity. Molecular screening of IDS identified three different pathogenic variants including a novel duplication variant c.114_117dupCGTT, a novel splice site variant c.1006 + 1G>C, and a nonsense variant c.1165C>T. In silico analysis unanimously revealed the pathogenic nature of the variants due to their deleterious effects upon the encoded enzyme. Conclusion: Identified variants predictably lead to either the expression of a nonfunctional enzyme due to partial loss of SD1 and complete loss of SD2 subdomains or a complete lack of the IDS enzyme as a result of nonsense-mediated mRNA decay. Our study provides the first genetic depiction of MPS-II in Pakistan, expands the global IDS mutation spectrum, may provide insights into the three-dimensional structure of IDS, and should benefit the affected families in genetic counseling and prenatal diagnosis. [ABSTRACT FROM AUTHOR]