Disease relevance of C1D

• The C1D gene was mapped to human chromosome 2, which frequently shows deletions in human follicular thyroid carcinomas [1].
• The nuclear DNA binding protein high mobility group 1 (HMGB1) protein has recently been suggested to act as a late mediator of septic shock via its function as a macrophage-derived pro-inflammatory cytokine (J Exp Med 2000; 192: 565, Science1999; 285: 248) [2].

High impact information on C1D

• Here, through use of the yeast two-hybrid screen, we discover that the recently identified high affinity DNA binding protein C1D interacts with the putative leucine zipper region of DNA-PKcs [3].
• Our study provides one of the first demonstrations of a eukaryotic, nuclear DNA-binding protein that is also on the cell membrane [4].
• PC4 is a nuclear DNA-binding protein that stimulates activator-dependent class II gene transcription in vitro [5].
• Characterization of SAF-A, a novel nuclear DNA binding protein from HeLa cells with high affinity for nuclear matrix/scaffold attachment DNA elements [6].
• Loss of RCC1, a nuclear DNA-binding protein, uncouples the completion of DNA replication from the activation of cdc2 protein kinase and mitosis [7].

Biological context of C1D

• Induction of apoptosis by overexpression of the DNA-binding and DNA-PK-activating protein C1D [8].
• The expression of this gene must be tightly regulated because elevated levels of C1D protein, e.g. those induced by transient vector-dependent expression, result in apoptotic cell death [8].
• Transient transfection experiments point to the presence of cis-acting repressing sequences on this LINE-1 element which reduce the transcriptional activity of the basal C1D promoter in human and murine cells by more than 95% [9].
• In our sample (n = 618) nine phenotypes, Tf C1, C2, C3, C3-1, C2-1, C3-2, C1B, C2B and C1D, were observed and the following frequencies calculated: TfC1 = 0.77837; TfC2 = 0.1804; TfC3 = 0.03641; TfB = 0.0040; TfD = 0.0008 [10].
• The v-jun oncogene encodes a nuclear DNA binding protein that functions as a transcription factor and is part of the activator protein 1 complex [11].

Anatomical context of C1D

• The nuclear matrix protein C1D is an activator of the DNA-dependent protein kinase (DNA-PK), which is essential for the repair of DNA double-strand breaks (DSBs) and V(D)J recombination [12].
• High Mobility Group Box chromosomal protein 1 (HMGB1) is a nuclear DNA-binding protein acting as a proinflammatory cytokine when released in the extracellular space from necrotic cells,activated macrophages and dendritic cells [13].
• Identification of alpha-enolase as a nuclear DNA-binding protein in the zona fasciculata but not the zona reticularis of the human adrenal cortex [14].
• Synthesis of a 60 kD nuclear DNA binding protein induced by cytosine arabinoside in the HL 60 leukemic cell line [15].
• Evidence was obtained that a nuclear DNA-binding protein, NF-E2, may be involved in the regulation of both hemoglobin synthesis in erythroid cells and of iron absorption in the intestine [16].

Associations of C1D with chemical compounds

• Sequence analysis revealed that this protein is C1D, the human homolog of the murine SUN-CoR protein which acts as a corepressor for the thyroid hormone receptor [1].
• The total hemolytic activity of this C1D could be increased to approximately 75% of that of the original serum by the addition of excess purified C1 [17].
• Serum depleted of the first component of complement (C1D) was prepared by treating fresh human serum with Sepharose-IgG in the presence of triethylenetetramine-N,N,N',N'',N''',N'''-hexa-acetic acid and di-isopropyl fluorophosphate at acidic pH (5.2) [17].
• C1 was removed from human serum by polyethylene glycol (PEG) precipitation and the supernatant (C1 deficient serum, C1D) was used for assay of C1 hemolytic activity (C1D method) [18].
• High-mobility group-1 (HMG-1), an abundant, highly conserved cellular protein, is widely known as a nuclear DNA-binding protein that stabilizes nucleosome formation, facilitates gene transcription, and regulates the activity of steroid hormone receptors [19].

Physical interactions of C1D

• In our previous reports we have described human nuclear DNA-binding protein interacting with AFRs and evidence was presented that the protein recognizes sequence motif 5'-GGAGGC-3' which is conserved in the spacer of RNA polymerase III promoter of AFRs and in the SV40 T-antigen-dependent replication origin of AFRs [20].

Regulatory relationships of C1D

• These results suggest that one role for C1D may be to regulate TRAX/Translin complex formation [12].

Other interactions of C1D

• We show that C1D and TRAX interact specifically in both yeast and mammalian cells [12].
• OBJECTIVE: High mobility group box chromosomal protein 1 (HMGB-1), a nuclear DNA binding protein, was recently rediscovered as a new proinflammatory cytokine [21].
• The human KIN (also known as KIN17) gene encodes a 45-kDa nuclear DNA-binding protein that participates in the response to UVC radiation and is immunologically related to the bacterial RecA protein [22].
• The human CCG1 gene, essential for progression of the G1 phase, encodes a 210-kilodalton nuclear DNA-binding protein [23].
• The nuclear DNA-binding protein DEK is an autoantigen that has been implicated in the regulation of transcription, chromatin architecture, and mRNA processing [24].

Analytical, diagnostic and therapeutic context of C1D

• Cell fractionation and column chromatography reveal that the Sp1 kinase is a nuclear DNA binding protein that corresponds to a previously identified DNA-dependent protein kinase [25].

References