Disease relevance of ZCCHC7

• RJ 2.2.5 is a human B cell mutant derived from the Burkitt lymphoma Raji cell which is defective in the AIR-1 locus function [1].
• This was unambiguously demonstrated by the fact that plasmacytoma x B cell hybrids carrying an AIR-1 locus derived from CIITA-expressing cells do not express CIITA-specific transcripts [2].
• Therefore, it is possible to hypothesize that variability at the CIITA-encoding locus, AIR-1, could constitute an additional source of susceptible traits to autoimmune diseases [3].

High impact information on ZCCHC7

• Here we show that the AIR-1-encoded human major histocompatibility complex (MHC) class II transactivator (CIITA) strongly inhibits viral replication, but not virus entry, in human B- and T-cell susceptible targets [4].
• In vivo modification of major histocompatibility complex class II DRA promoter occupancy mediated by the AIR-1 trans-activator [1].
• RJ 2.2.5 is a human B cell mutant, derived from Raji cells, which has lost expression of major histocompatibility complex (MHC) class II genes because of a defect in the AIR1 locus function [5].
• The MHC class II-positive phenotype can be restored by introducing an active AIR1 locus or its mouse equivalent, Air-1 [5].
• Effect of the AIR-1 locus on the activation of an enhancerless HLA-DQA1 promoter [6].

Biological context of ZCCHC7

• HLA class II expression in uninducible hepatocarcinoma cells after transfection of AIR-1 gene product CIITA: acquisition of antigen processing and presentation capacity [7].
• The expression of HLA class II genes is under the control of a transcriptional activator, CIITA, encoded by the AIR-1 locus [8].
• The fact that this promoter is inactive in the RJ2.2.5 mutant suggests that the trans-acting element determined by the AIR-1 locus is not only an enhancer factor as previously described, but also acts at the MHC class II promoter level [6].

Anatomical context of ZCCHC7

• Studies on the regulation of a major histocompatibility complex (MHC) class II gene, HLA-DQA1, in Ia-positive cells (Raji, a human B-lymphoma cell line) and in isogenic Ia-negative cells (RJ2.2.5, a mutant of Raji altered at the AIR-1 locus) are reported [6].
• Robust MT nucleation by centrosomes requires AIR-1, SPD-2, SPD-5, and gamma-tubulin [9].

Other interactions of ZCCHC7

• The AIR-1 encoded class II transactivator (CIITA): the master coordinator of MHC class II gene expression and .. more [10].

References