Pre-B-cell leukemia transcription factor 1 is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''PBX1''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
. The homologous protein in Drosophila is known as extradenticle, and causes changes in embryonic development.
Function
Mice studies suggest PBX1 is involved in bone generation and skeletal patterning.
Interactions
PBX1 has been shown to
interact with:
*
HOXB1,
*
HOXB7,
*
MEIS1,
and
*
Prep1.
Fruit fly homolog
The
''Drosophila melangoster'' gene called ''extradenticle'' encodes a homeodomain protein that is 71% similar to the Pbx1 protein, and is considered homologous to PBX1.
extradenticle is a
homeodomain transcription factor expressed during
embryogenesis
An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male ...
and is related to morphological changes and development.
Reduced levels of extradenticle cause segmental transformations, without affecting the functionality or location of
homeotic genes. Complete removal of extradenticle both maternally and zygotically leads to alterations from failure of non-extradenticle protein expression.
A monoclonal antibody study of the expression of extradenticle protein in embryonic development found that it is uniformly distributed, as well as excluded from cell nuclei, until
gastrulation
Gastrulation is the stage in the early embryonic development of most animals, during which the blastula (a single-layered hollow sphere of cells), or in mammals, the blastocyst, is reorganized into a two-layered or three-layered embryo known as ...
. During the germ band retraction stage of development, extradenticle protein begins to accumulate in the nuclei of cells in a specific pattern. Proximal areas of wing and leg
imaginal discs have extradenticle present in the nucleus, while distal areas only have it in the cytoplasm.
References
Further reading
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
External links
*
*
*
{{Transcription factors, g3
Transcription factors