Structural Analysis of hypothetical protein Accession No CAI56786.1 of Homo sapiens

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Bioinformatics has been serving to identify many unknown sequences and bring their importance into lime light. The methodology used here is the comparative study of the unknown sequence with the known sequences in the database thereby annotating the unknown sequence. The aim of the current was to charecterize and annotates a Hypothetical human protein with accession no CAI56786.1 obtained from NCBI database using various insilico tools and software. Several approaches have been made for predicting protein structure and function using the information derived from sequence similarity, phylogenetic profiles, protein domains etc. The classical way to infer function is based on sequence similarity using sequence database searching programs such as FASTA and PSI-BLAST, CLUSTAL W, to find out SNPs and close similarities with other species. SMART tool has been used to predict domain identification, Protparam for physical and chemical properties of protein. Secondary structure prediction was done using SOPMA, 3D structure was visualized using Rasmol software.


A hypothetical protein is a protein that is predicted to be expressed from an open reading frame, but for which there is no experimental evidence of translation. Hypothetical proteins constitute a substantial fraction of proteomes of human as well as of other eukaryotes. With the general belief that the majority of hypothetical proteins are the product of pseudogenes, it is essential to have a tool with the ability of pinpointing the minority of hypothetical proteins with a high probability of being expressed.
Here, we present an in silico selection strategy where eukaryotic hypothetical proteins are sorted according to two criteria that can be reliably identified in silico: the presence of subcellular targeting signals and presence of characterized protein domains. To validate the selection strategy we applied it on a database of human hypothetical proteins dating to 2006 and compared the proteins predicted to be expressed by our selecting strategy, with their status in 2008. For the comparison we focused on mitochondrial proteins, since considerable amounts of research have focused on this field in between 2006 and 2008. Therefore, many proteins, defined as hypothetical in 2006, have later been characterized as mitochondrial.


In the above work the structure analysis of hypothetical protein (homo sapiens) CAI56786 was performed, Structure of hypothetical protein may provide a hint for their biochemical or biophysical functions. 3D structure can aid the assignment of function for the characterization ofprotein.The multiple sequence alignmentwith the query sequence shows conserved as well as some SNPs regions which are in significant. The structure of protein shows multiple PDZ domains which can be predicted as a significant functional protein.


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