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Sequence complexity of amyloidogenic regions in intrinsically disordered human proteins.

ABSTRACT: An amyloidogenic region (AR) in a protein sequence plays a significant role in protein aggregation and amyloid formation. We have investigated the sequence complexity of AR that is present in intrinsically disordered human proteins. More than 80% human proteins in the disordered protein databases (DisProt+IDEAL) contained one or more ARs. With decrease of protein disorder, AR content in the protein sequence was decreased. A probability density distribution analysis and discrete analysis of AR sequences showed that ?8% residue in a protein sequence was in AR and the region was in average 8 residues long. The residues in the AR were high in sequence complexity and it seldom overlapped with low complexity regions (LCR), which was largely abundant in disorder proteins. The sequences in the AR showed mixed conformational adaptability towards ?-helix, ?-sheet/strand and coil conformations.

SUBMITTER: Das S

PROVIDER: S-EPMC3940659 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Sequence complexity of amyloidogenic regions in intrinsically disordered human proteins.

Das Swagata S Pal Uttam U Das Supriya S Bagga Khyati K Roy Anupam A Mrigwani Arpita A Maiti Nakul C NC

PloS one 20140303 3

An amyloidogenic region (AR) in a protein sequence plays a significant role in protein aggregation and amyloid formation. We have investigated the sequence complexity of AR that is present in intrinsically disordered human proteins. More than 80% human proteins in the disordered protein databases (DisProt+IDEAL) contained one or more ARs. With decrease of protein disorder, AR content in the protein sequence was decreased. A probability density distribution analysis and discrete analysis of AR se ...[more]

PMID: 24594841

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