Differential expression and interaction of transcription co-activator MBF1 with TATA-binding protein (TBP) in the apicomplexan Cryptosporidium parvum.
All gene-specific transcriptional activators initiate gene transcriptions by binding to promoter sequences and recruiting general transcription factors including TATA-binding protein (TBP) to upstream of targeted genes. Some of them require multiprotein bridging factors (MBFs); for example, the type 1 MBF (MBF1) which interconnects the gene activator with TBP. In this study, the properties of a previously cloned type 1 multiprotein bridging factor (CpMBF1) and a newly identified TBP (CpTBP1) from the apicomplexan Cryptosporidium parvum were investigated. Genes encoding both proteins were differentially expressed as determined by semi-quantitative RT-PCRs during the parasite life cycle, but in different patterns. The highest level of expression of CpMBF1 was in the well-developed intracellular parasites, whereas that of CpTBP1 was found in intact oocysts and late intracellular stages, possibly correlated with the formation of oocysts. Both CpMBF1 and CpTBP1 were expressed as maltose-binding protein fusion proteins. The function of CpTBP1 was confirmed by its ability to bind a biotinylated DNA oligonucleotide containing TATA consensus sequence. The interaction between CpMBF1 and CpTBP1 was also observed by an electrophoretic mobility shift assay. Since little is known about the regulation and control of gene activity in C. parvum, this study may point to a new direction for the study of gene activation associated with the development of the complex life cycle of this parasite.
Millership
Jason J
JJ
Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.
Waghela
Palvi
P
Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.
Cai
Xiaomin
X
Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.
Cockerham
Amy
A
Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.
Zhu
Guan
G
Faculty of Genetics Program, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.|Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, TX 77843, USA.
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002417:Cattle; D017124:Conserved Sequence; D016785:Cryptosporidium parvum / Q000254:growth & development* / Q000378:metabolism / Q000472:pathogenicity; D005786:Gene Expression Regulation; D006801:Humans; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D033661:Oocysts / Q000378:metabolism*; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D035181:TATA-Box Binding Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
D002352:Carrier Proteins; D058619:Maltose-Binding Proteins; D015800:Protozoan Proteins; D011993:Recombinant Fusion Proteins; D035181:TATA-Box Binding Protein; D015534:Trans-Activators