Gene model reviewed during 5.41
Gene model reviewed during 5.46
Gene model reviewed during 5.55
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Hsp23 using the Feature Mapper tool.
At embryonic stage 11, Hsp23 transcript is expressed in MP2 neuroblasts, one laterally localized chordotonal organ precursor per hemisegment, and in the amnioserosa. By stage 13, Hsp23 transcript is expressed in one laterally localized chordotonal neuron per abdominal hemisegment, and one dorsally localized chordotonal neuron in the second and third thoracic segments. It is also expressed in the dMP2, vMP2 and VUM neurons. Expression in midline glial cells begins during stage 13, and expression becomes restricted to midline glial cells by late embryonic stages.
At embryonic stage 11, Hsp23 protein is expressed in MP2 neuroblasts, one laterally localized chordotonal organ precursor per hemisegment, and in the amnioserosa.By stage 13, Hsp23 protein is expressed in one laterally localized chordotonal neuron per abdominal hemisegment, and one dorsally localized chordotonal neuron in the second and third thoracic segments. It is also expressed in the dMP2, vMP2 and VUM neurons.. Expression in midline glial cells begins during stage 13, and expression becomes restricted to midline glial cells by late embryonic stages.
GBrowse - Visual display of RNA-Seq signalsView Dmel\Hsp23 in GBrowse 2
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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.
Area matching Drosophila HSP23 (inverted), Acc. No. X03889.
Heat shock does not appreciably affect the expression pattern of the small heat shock proteins and the same cell-specific pattern is observed after heat shock. Hsp23 and Hsp27 show cell-specific pattern of expression in the testes, the relative amount of Hsf also varies in the different cell types. Cells that do not express the proteins in the absence of stress are similarly unable to mount a heat shock response.
Analysis of Hsp23 5' sequences demonstrates the EcR element, although necessary, is not sufficient for the full ecdysone-responsive expression of Hsp23 in late third instar larvae. A second regulatory element localised at position -1400 is required.
The ecdysone responsive element is necessary but not sufficient for full hormone-induced expression of Hsp23 in the late third instar salivary glands.
DNase hypersensitive sites (DHS) in the 5' regions of Hsp27 and Hsp23 are mapped in salivary glands developmentally exposed to ecdysone during larval-prepupal transition. The DHSs reveal the sites that correlate with the hormonal induction of tissue-specific expression.
Synthesis of heat shock proteins is inhibited by both short-chain fatty acids and their corresponding alcohols, compounds which have no observable effect on histone acetylation.
In vivo UV cross-linking and nuclear run-on assays shows that RNA polymerase II density on the Hsp23 gene is rapidly increased by heat shock.
In unshocked cells Hsp83 is moderately transcribed while transcription from the other heat shock genes is undetectable. Engaged but paused RNA molecules are found at the various Hsp70 and Hsp26 genes but not at the other heat shock genes. Increased transcription of the heat shock genes is observed within 1-2 mins of heat shock and maximal rates were reached within 2-5 minutes. Rates of transcription vary over a 20-fold range.
Exposure of cells to pulses of elevated temperature initiates the heat-shock response. A restricted subset of genes, the Hsp genes, is activated and the majority of transcription and translation is shut down. 3H-uridine incorporation ceases at its usual positions and commences at new puff sites. Preexisting polysomes disaggregate and within a few minutes a new population of polysomes appears containing newly transcribed mRNA; this RNA hybridizes to some of the heat-shock puffs. Similar response inducible by other stressful treatments. The response may be elicited at all stages of the life cycle and in cultured cells.
Translation of Hsp70 mRNAs and to a lesser extent the mRNAs for the small heat shock proteins is almost independent of eIF-4E.
Mutations at br reduce the transcription rate or stability of the small heat shock protein mRNAs.
The binding sites for the protein factors required for activation of transcription of Hsp genes are multiple short upstream sequence elements called HSEs or heat shock consensus elements.
Heat-shock inducible in almost all cells at the stages tested.
Activation of transcription of Hsp genes apparently involves the sequential binding of two or more protein factors in vicinity of TATA box.
Polymerase II dissociates from most chromosome regions and accumulates at the new heat shock puff sites upon heat shock.
Hsp23 is transcribed during certain developmental stages in the absence of heat shock.
The effects of heat shock may be abrogated to some degree by pretreatment with a pulse of a slightly lower temperature.
Mitochondrial and histone-gene activities persist transcription and translation.
In polytene cells, during heat shock response, existing puffs regress and a novel group quickly appear at 33B, 63C, 64F, 67B, 70A, 87A, 87C, 93D, 95D.
The heat shock response follows a pulse of 36oC to 40oC; treatments above 40oC inhibit all activity and lead to death; treatments of 30oC-35oC induce heat-shock-protein synthesis without repressing normal protein synthesis.
In polytene cells, during heat shock response, existing puffs regress and a novel group quickly appear at cytological locations 33B, 63C, 64F, 67B, 70A, 87A, 87C, 93D, 95D.