expression is generally consistent over this time period, with slight peaks at 6h and 24h APF.
transcripts are differentally expressed during oogenesis. kay
-RA transcript is expressed in nurse cells from oogenesis stage 5 through stage 9. kay
-RB transcription is first detected at oogenesis stage 9 in migrating columnar cells, with weak to no expression in anterior stretching cells posterior follicle cells. During early stage 10A kay
-RB transcript levels decrease sharply and is transiently restricted to the anterior-most columnar cells before disappearing completely at mid-stage 10A. At early stage 10B, kay
-RB transcript is strongly expressed in anterior stretched cells. From late stage 10B, kay
-RB transcript accumulates to a high level in two rows of dorsal anterior follicle cells. During stage 13,kay
-RB transcript is strongly expressed in a population of approximately 15 follicle cells located at the posterior pole of the oocyte. kay
-RA transcript is uniformly distributed in preblastoderm embryos; this transcript is maternally deposited. kay
-RB, by contrast, is not maternally deposited. Both kay
transcripts are zygotically expressed at embryonic stage 4, in the amnioserosa anlage, and both continue to be expressed in the amnioserosa, and later in the embryonic leading edge cells. kay
-RA is additionally expressed in the cephalic and posterior transverse furrows during gastrulation. kay
-RB is additionally expressed in the stomodeal invagination, and in the cells that go on to form midgut constriction 1.
transcript is expressed strongly in salivary glands at the beginning of the prepupal ecdysone pulse (10 hr APF).
transcripts are detected at a low level on northern blots in 4-8hr embryos and at a higher level in 8-12 and 12-16hr embryos. kay
expression was shown to be restricted to certain cell types by in situ hybridization. It is expressed in cells of the head that are thought to be mesodermal soon after gastrulation (4-5hr) and persists until 8hr of embryogenesis. Early expression is also observed in the dorsal ectoderm and the amnioserosa. After ~11hr of embryogenesis, expression is restricted to a subset of PNS cells. They localize near the lateral chordotonal organs and may be the es (extrasensory) or md (multiple dendritic) neurons. Later expression is also observed in the muscle attachment sites, midgut, hindgut, and anal pads.