At the cellular blastoderm stage (2.5 hours), Ten-m
protein is visible at the periphery of cells, suggesting a plasma-membrane associated or extracellular localization.
At embryonic stage 8, Ten-m
(as well as cher
), is expressed in all furrows and in the posterior midgut. It is expressed in a repetitive pattern at stage 11. By stage 13, it is epressed in the ventral nerve cord. At stage 15, Ten-m
is expressed in the axons of the CNS. It is expressed in bands of epidermal cells at segmental boundaries, where it colocalizes with cher
is expressed posterior to the morphogenetic furrow in the third instar eye disc, and as point-like expression in more mature developing ommatidia. At higher resolutions, Ten-m
can be seen in four staggered columns of preclusteres after the furrow, at the periphery of cells.
protein is expressed in a complex pattern of the eye-antennal disc in the third instar larva. Protein is distributed in in a row of cells in the morphogenetic furrow, and in two rows posterior to the furrow; staining in these cells is uniform, and consistant with a cell surface distribution. No staining is observed for another 10 cell diameters, after which Ten-m
expression is observed in a single cell, likely the R7 photoreceptor cell, of each maturing ommatidium. Expression is also observed in the optic stalk, and in two clusters of adepithelial cells, one in the eye disc and one in the antennal disc. Expression in the antennal disc is observed in the presumptive maxillary palpus, in the presumptive antennal segments, in the presumptive head capsule, and in the presumptive rostral membrane.
protein is expressed in a complex pattern in the wing disc. In the wing pouch, it is expressed in two hook-shaped contiguous lines of expression in apposing patterns on either side of the dorsal/ventral boundary; a portion of each parallels about a quarter of the dorsal/ventral boundary at a distance of 3-4 cell lengths, then turns to follow the anterior/posterior boundary at about the location of the presumptive third longitudinal wing vein. Expression is also observed in the presumptive first, third, and fourth axillary sclerites, in the presumptive prealar apophysis, the presumptive pleural wing process, the presumptive yellow club, the presumptive pleural wing sclerite, and in the dorsal tissue giving rise to the proximal dorsal radius and the sensilla campaniformia that cover it. Expression is also observed in the presumptive proximal costal vein, in the presumptive prescutum and scutum, in the presumptive anterior and posterior notal wing processes, the presumptive tegula, the presumptive alula, the presumtive axillary cord, and in the regions of presumptive pleura adjacent to the wing.
protein expression is strong in the regions of the haltere disc that give rise to the sensilla of the dorsal and ventral pedicel, and of dorsal and ventral scabellum. Ten-m
protein is distributed in concentric rings in the leg discs, corresponding to the segments of the adult leg.
protein is present uniformly in the anterior-posterior axis, and in an anterior domain in stage 5 embryos, but by stage 6, a repetitive pattern comprising seven full stripes and two partial stripes are visible. By stage 8, Ten-m
protein is present in the anterior and posterior transverse furrows, and in the posterior midgut primordia, with decreasing staining in the ectoderm. By stage 9, Ten-m
protein is only visible in the mesoderm. At stage 10, the neuroblasts of the procephalic lobe stain for Ten-m
protein, and from stage 12 to 15 Ten-m
protein is visible in the axons of the ventral nerve cord. At stage 11, staining in the tracheal system becomes visible. At stages 12-13, staining is also seen in cardiac cells. At stage 16, muscle attachment sites show staining.
The 7 stripe segmentally repeated pattern of Ten-m
protein expression in 2.5 to 3.5 hour embryos is followed by a 14-stripe segmentally repeated pattern of expression at 4.5 to 7.5 hours. The most intense segmentally repeated staining is seen in the mesoderm. At 9.5 hours, Ten-m
protein is found in cardiac mesoderm cells, which will become cardioblasts. Also at 9.5 hours, and continuing through embryogenesis, is central nervous system staining of longitudinal and commissural axon tract bundles.