Pax family transcription factor - demarcates the 'Poxm competence domain', a domain of competence for ventral and lateral muscle development and for the determination of at least some adult muscle precursor cells
Gene model reviewed during 5.49
There is only one protein coding transcript and one polypeptide associated with this gene
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Poxm using the Feature Mapper tool.
Poxm transcripts are observed in a segmental pattern during the later stages of germ band elongation. They are observed in the posterior half of each segment and are restricted to the mesodermal germ layer. Apart from the repetitive pattern of cells expressing Poxm in parasegments 3-14, groups of cells in the labral segment, the cephalic mesoderm, the telson, and proctodeal primordia also express Poxm.
Poxm is first detected in the somatic mesoderm at embryonic stage 10. During stage 10, it is expressed in segmentally repeated mesodermal stripes underlying the ectodermal parasegments 2-14, in the head mesoderm, the proctodeal anlage, and in a group of ectodermal cells from the clypeolabrum, which are thought to correspond to part of the esophagus anlage. Poxm is expressed in the high twi domain in the lateral and ventral mesoderm. Its expression is repressed in the dorsal portion of each segment by dpp. The number of Poxm-expressing cells increases with distance from the dorsal margin, forming a triangular pattern. Its expression domain is complementary to that of tin. During stage 11, Poxm expression is restricted to fewer cells, some of which will form subsets of muscle progenitors and cells of the promuscular clusters. During germband retraction, Poxm disappears from the most anterior mesodermal stripe and the telson. By stage 12, Poxm expression is maintained in only six cells in each of the abdominal segments A1-7. These are the founder cells of DO3, DT1, VA1-3, and the ventral adult muscle precursor. At this time more cells express Poxm in the thoracic segments than in the abdominal segments. As myoblast fusion proceeds during stage 13, the number of Poxm nuclei increases as it is expressed in the precursors of muscles DT1 and VA1-3. During stage 14, Poxm expression begins to be reduced in ventral clusters and in the dorsolater regions from which it disappears during stage 16 and is gone by stage 17. Outside of the mesoderm, high levels of Poxm are observed in the esophagus and hindgut throughout embryogenesis.
GBrowse - Visual display of RNA-Seq signalsView Dmel\Poxm in GBrowse 2
Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see GBrowse for alignment of the cDNAs and ESTs to the gene model.
For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.
Source for identity of: Pox-m CG9610
The early function of Poxm during myogenesis, which is partially redundant with the function of l(1)sc, demarcates a domain of competence for ventral and lateral muscle development and for the determination of at least the VA1, VA2 and VA3 muscles. The late function of Poxm is a muscle identity function, required for the specification of muscles DT1, VA1, VA2 and VA3.
Poxm was isolated as it shared a network specific domain with prd that specifies position along the antero posterior axis of the embryo.
tissue-specific Drosophila paired box gene lacking homeodomains. No mutants have been discovered.
Poxm shows tissue-specific, segmentally-repeated expression in the somatic mesoderm, starting at germ band extension. Transcripts are observed posterior to the parasegmental grooves (restricted to the mesodermal layer). The protein has been observed by immunostaining in the somatopleura that gives rise to the somatic musculature, but is not found in the splanchnopleura and the mesectodermal cells (Jamet). Groups of cells in the clypeolabrum, the cephalic mesoderm and the primordia of the telson and the proctodeum also express Poxm.