What does HOXA9 do?
HOXA9 is a homeodomain-containing transcription factor that has an important role in hematopoietic stem cell expansion and is commonly deregulated in acute leukemias. A variety of upstream genetic alterations in acute myeloid leukemia lead to overexpression of HOXA9, which is a strong predictor of poor prognosis.
How does transcription factor recognize promoter?
Transcription factors recognize and bind to specific DNA sequences called promotor or enhancer sequences. Other transcription factors called activators target enhancer sequences that initiate the bending of the DNA to allow interaction with the proteins bound to the promoter region.
Do transcription factors have promoters?
transcription factor / transcription factors One distinct feature of transcription factors is that they have DNA-binding domains that give them the ability to bind to specific sequences of DNA called enhancer or promoter sequences.
What is a homeodomain protein?
The homeodomain is a common DNA-binding structural motif found in many eukaryotic regulatory proteins (1,2). Homeodomain proteins are involved in the transcriptional control of many developmentally important genes, and 143 human loci have been linked to various genetic and genomic disorders.
What are promoters in transcription?
Promoter. = A promoter is a sequence of DNA needed to turn a gene on or off. The process of transcription is initiated at the promoter. Usually found near the beginning of a gene, the promoter has a binding site for the enzyme used to make a messenger RNA (mRNA) molecule.
What are homeodomain transcription factors?
Homeodomain proteins are transcription factors that play major roles in many developmental processes of animals and plants by regulating the expression of other genes during development and differentiation, and are responsible for mating-type switching in yeast.
What is helix loop helix motif?
A basic helix–loop–helix (bHLH) is a protein structural motif that characterizes one of the largest families of dimerizing transcription factors. bHLH transcription factors are often important in development or cell activity.
What binds to the promoter sequence?
RNA polymerase and the necessary transcription factors bind to the promoter sequence and initiate transcription. Promoter sequences define the direction of transcription and indicate which DNA strand will be transcribed; this strand is known as the sense strand.
How does HOXA9 regulate the downstream gene expression?
Recent work has established that HOXA9 regulates downstream gene expression through binding at promoter distal enhancers along with a subset of cell-specific cofactor and collaborator proteins.
What is the role of HOXA9 in carcinoma?
HOXA9 acts as an oncogene in laryngeal squamous cell carcinoma, promoting tumor cell proliferation and migration. SALL4 binds a specific region of the HOXA9 promoter in leukemic cells.
Why is HOXA9 downregulated in leukaemia cells?
Downregulation of HOXA9 in myeloid leukaemia cells led to increased differentiation capacity in vitro. Based on the human, animal and cellular data, the transcription factor HOXA9 may promote the expression of pro-myopia genes and retinal pigment epithelial proliferation, which eventually contribute to myopia development.
Which is a novel regulator of the HOXA9 program?
MicroRNA-708 is a novel regulator of the Hoxa9 program in myeloid cells. HOXA9 rs3801776 G>A polymorphism increases congenital talipes equinovarus risk in a Chinese population. MicroRNA-652-3p promotes the proliferation and invasion of the trophoblast HTR-8/SVneo cell line by targeting homeobox A9 to modulate the expression of ephrin receptor B4