Disease relevance of MYCBP

• MM-1, a c-Myc-binding protein, is a candidate for a tumor suppressor in leukemia/lymphoma and tongue cancer [1].
• We found that mRNAs encoding for cyclophilin A, c-myc binding protein 1, the heat shock protein 90alpha and one unknown transcript were up-regulated in the oral cancer cell lines analysed as well as in HOK-16B cells [2].

High impact information on MYCBP

• These results suggest that both AAT-1 and AMY-1 play roles in spermatogenesis [3].
• AAT-1alpha was found to bind to and be colocalized in mitochondria with AMY-1 in human HeLa and mouse GC-1 cells [3].
• AAT-1 was found to be specifically expressed in the testis during the course of spermatogenesis and also to be present in the spermatid and mature sperm, as was AMY-1 [3].
• It was also found that the formation of the complex of AMY-1 with AKAP84/95 and RII prevented a catalytic subunit from binding to this AKAP complex, leading to suppression of PKA activity [4].
• We have reported that a novel c-Myc-binding protein, AMY-1 (associate of Myc-1), stimulated the transcription activity of c-Myc [5].

Biological context of MYCBP

• AMY-1, which mostly localizes in the cytoplasm, translocates into the nucleus in the S phase of the cell cycle upon an increase of c-myc expression, and may thus control the transcriptional activity of C-MYC [6].
• AMY-1 was bound via its C-terminal region to the N-terminal region of C-MYC (amino acids nos 58-148) corresponding to the transactivation domain [6].
• AMY-1 by itself did not recognize the E-box element, the MYC/Max binding sequence, nor did it transactivate via the element, but stimulated the activation of E-box-regulated transcription by MYC/Max [6].
• We have isolated the cDNA encoding a novel c-Myc-binding protein, MM-1, by the yeast two-hybrid screening of a human HeLa cell cDNA library [7].
• AMY-1 works as an inducer of human K562 cell differentiation upon induction of AraC [8].

Anatomical context of MYCBP

• AMAP-1 was found to be specifically expressed in the testis and expressed post-meiotically in the testis, as was AMY-1 [9].
• AMY-1 was found to bind to and be colocalized with AMAP-1 in human 293T and HeLa cells [9].
• We show here that, using anti-AMY-1 antibodies we raised, AMY-1 localizes to the trans-Golgi network (TGN) and the nucleus [10].
• The results showed that Sp1 was essential for AMY-1 expression in both cell lines and that GATA-1 is also necessary in K562 cells [8].
• AMY-1 is a trigger for the erythrocyte differentiation of K562 cells [11].

Associations of MYCBP with chemical compounds

• AMY-1 (associate of Myc-1) localization to the trans-Golgi network through interacting with BIG2, a guanine-nucleotide exchange factor for ADP-ribosylation factors [10].
• In addition, c-myc binding protein and apoptosis-related cysteine proteases caspase-3 and caspase-8 were also regulated [12].

Physical interactions of MYCBP

• All of the isoforms of AAT-1 were found to bind to and colocalized with AMY-1 in human cells [13].

Regulatory relationships of MYCBP

• AMY-1, a novel C-MYC binding protein that stimulates transcription activity of C-MYC [6].
• We showed that the expression of c-myc binding protein (MYCBP) in colon carcinoma cells was consistently upregulated by overexpressed LEF-1, which is confirmed by microarray data, RT-PCR and luciferase assay [14].

Other interactions of MYCBP

• Identification of MYCBP as a beta-catenin/LEF-1 target using DNA microarray analysis [14].

Analytical, diagnostic and therapeutic context of MYCBP

• To explore the possible function of AMY-1, we have undertaken a search for interacting partners by co-immunoprecipitation experiments using cells stably expressing FLAG-tagged AMY-1 [10].
• The isl-1 homeodomain binds to the AT-rich AMY element (-156 to -137) in the human amylin (hAMY) gene promoter, and electrophoretic mobility shift assay experiments using isl-1 specific antiserum detected the formation of an hAMY-isl-1 complex using nuclear extract from InR1 -G9 islet cells [15].
• An alternative method for AMY1 typing by means of isoelectric focusing is proposed which allows the use of long-term stored saliva samples [16].

References