Abstract
Compaction of DNA into chromatin is a characteristic feature of eukaryotic organisms. The core (H2A, H2B, H3, H4) and linker (H1) histone proteins are responsible for this compaction through the formation of nucleosomes and higher order chromatin aggregates. Moreover, histones are intricately involved in chromatin functioning and provide a means for genome dynamic regulation through specific histone variants and histone post-translational modifications. ‘HistoneDB 2.0 – with variants’ is a comprehensive database of histone protein sequences, classified by histone types and variants. All entries in the database are supplemented by rich sequence and structural annotations with many interactive tools to explore and compare sequences of different variants from various organisms. The core of the database is a manually curated set of histone sequences grouped into 30 different variant subsets with variant-specific annotations. The curated set is supplemented by an automatically extracted set of histone sequences from the non-redundant protein database using algorithms trained on the curated set. The interactive web site supports various searching strategies in both datasets: browsing of phylogenetic trees; on-demand generation of multiple sequence alignments with feature annotations; classification of histone-like sequences and browsing of the taxonomic diversity for every histone variant. HistoneDB 2.0 is a resource for the interactive comparative analysis of histone protein sequences and their implications for chromatin function.Database URL: http://www.ncbi.nlm.nih.gov/projects/HistoneDB2.0
Highlights
Nucleosomes constitute the elementary building blocks of chromatin and play important functional roles in epigenetic regulation of transcription, replication, cell development and reprogramming
Each nucleosome core particle consists of about 147 base pairs of DNA wrapped around an octamer of histone proteins—two copies of H3, H4, H2A and H2B [1, 2]
The linker histone H1 usually binds to the nucleosome core and linker DNA to form ‘chromatosomes’ and promotes further chromatin compaction
Summary
Nucleosomes constitute the elementary building blocks of chromatin and play important functional roles in epigenetic regulation of transcription, replication, cell development and reprogramming. Each histone variant has characteristic sequence and structural features that account for its specific function. We present a database ‘HistoneDB 2.0 – with Variants’ that collects canonical histones and histone variants, their sequence, structural and functional features.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
