Biomaterial Database

Dual recognition of CENP-A nucleosomes is required for centromere assembly. 2010

Christopher W Carroll, and Kirstin J Milks, and Aaron F Straight

Department of Biochemistry, Stanford University School of Medicine, Palo Alto, CA 94503, USA.

Centromeres contain specialized nucleosomes in which histone H3 is replaced by the histone variant centromere protein A (CENP-A). CENP-A nucleosomes are thought to act as an epigenetic mark that specifies centromere identity. We previously identified CENP-N as a CENP-A nucleosome-specific binding protein. Here, we show that CENP-C also binds directly and specifically to CENP-A nucleosomes. Nucleosome binding by CENP-C required the extreme C terminus of CENP-A and did not compete with CENP-N binding, which suggests that CENP-C and CENP-N recognize distinct structural elements of CENP-A nucleosomes. A mutation that disrupted CENP-C binding to CENP-A nucleosomes in vitro caused defects in CENP-C targeting to centromeres. Moreover, depletion of CENP-C with siRNA resulted in the mislocalization of all other nonhistone CENPs examined, including CENP-K, CENP-H, CENP-I, and CENP-T, and led to a partial reduction in centromeric CENP-A. We propose that CENP-C binds directly to CENP-A chromatin and, together with CENP-N, provides the foundation upon which other centromere and kinetochore proteins are assembled.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009707	Nucleosomes	The repeating structural units of chromatin, each consisting of approximately 200 base pairs of DNA wound around a protein core. This core is composed of the histones H2A, H2B, H3, and H4.	Dinucleosomes,Polynucleosomes,Dinucleosome,Nucleosome,Polynucleosome
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002503	Centromere	The clear constricted portion of the chromosome at which the chromatids are joined and by which the chromosome is attached to the spindle during cell division.	Centromeres
D002843	Chromatin	The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.	Chromatins
D002868	Chromosomal Proteins, Non-Histone	Nucleoproteins, which in contrast to HISTONES, are acid insoluble. They are involved in chromosomal functions; e.g. they bind selectively to DNA, stimulate transcription resulting in tissue-specific RNA synthesis and undergo specific changes in response to various hormones or phytomitogens.	Non-Histone Chromosomal Proteins,Chromosomal Proteins, Non Histone,Chromosomal Proteins, Nonhistone,Non-Histone Chromosomal Phosphoproteins,Chromosomal Phosphoproteins, Non-Histone,Non Histone Chromosomal Phosphoproteins,Non Histone Chromosomal Proteins,Nonhistone Chromosomal Proteins,Proteins, Non-Histone Chromosomal
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000076247	Centromere Protein A	A 17 kDa, centromeric, poly(ADP)-ribose binding protein that is structurally similar to HISTONE H3 and localizes to NUCLEOSOMES within the CENTROMERE; specifically within the region that binds KINETOCHORES, where it replaces histone H3. It plays a critical role in recruiting kinetochore proteins and progression through MITOSIS, chromosome segregation, and CYTOKINESIS. It also binds sera from patients with some scleroderma-like AUTOIMMUNE DISEASES.	CENP-A Protein,CENPA Protein,Centromere Autoantigens 17K,Centromere Protein 17K,Autoantigens 17K, Centromere,CENP A Protein
D001324	Autoantigens	Endogenous tissue constituents with the ability to interact with AUTOANTIBODIES and cause an immune response.	Autoantigen,Autologous Antigen,Autologous Antigens,Self-Antigen,Self-Antigens,Antigen, Autologous,Antigens, Autologous,Self Antigen,Self Antigens
D034741	RNA, Small Interfering	Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.	RNA, Scan,Repeat-Associated siRNA,Scan RNA,Small Scan RNA,Trans-Acting siRNA,siRNA,siRNA, Repeat-Associated,siRNA, Trans-Acting,Short Hairpin RNA,Short Interfering RNA,Small Hairpin RNA,Small Interfering RNA,scnRNA,shRNA,tasiRNA,Hairpin RNA, Short,Hairpin RNA, Small,Interfering RNA, Short,Interfering RNA, Small,RNA, Short Hairpin,RNA, Short Interfering,RNA, Small Hairpin,RNA, Small Scan,Repeat Associated siRNA,Scan RNA, Small,Trans Acting siRNA,siRNA, Repeat Associated,siRNA, Trans Acting