Dpbx, lincRNA.S9404
TALE-class homeodomain transcription factor - cooperatively interacts with homeotic proteins to increase the specificity of homeotic protein binding to DNA - Engrailed cooperates directly with Extradenticle and Homothorax on a distinct class of homeodomain binding sites to repress - controls dendritic and axonal targeting of olfactory projection neurons in the brain - control adult muscle fiber identity
Please see the JBrowse view of Dmel\exd for information on other features
To submit a correction to a gene model please use the Contact FlyBase form
AlphaFold produces a per-residue confidence score (pLDDT) between 0 and 100. Some regions with low pLDDT may be unstructured in isolation.
Gene model reviewed during 5.50
Low-frequency RNA-Seq exon junction(s) not annotated.
Annotated transcripts do not represent all supported alternative splices within 5' UTR.
Gene model reviewed during 5.46
Tissue-specific extension of 3' UTRs observed during later stages (FBrf0218523, FBrf0219848); all variants may not be annotated.
Gene model reviewed during 5.52
3.4, 2.8 (northern blot)
376 (aa); 41.7 (kD)
Interacts with Ubx and hth.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\exd using the Feature Mapper tool.
Comment: maternally deposited
Comment: anlage in statu nascendi
Comment: anlage in statu nascendi
Comment: anlage in statu nascendi
Comment: anlage in statu nascendi
Comment: reported as procephalic ectoderm anlage
Comment: reported as procephalic ectoderm anlage
Comment: reported as procephalic ectoderm anlage
Comment: reported as procephalic ectoderm anlage
Comment: reported as ventral nerve cord anlage
Comment: reported as procephalic ectoderm primordium
Comment: reported as procephalic ectoderm primordium
Comment: reported as procephalic ectoderm primordium
Comment: reported as procephalic ectoderm primordium
Comment: reported as procephalic ectoderm primordium
Comment: reported as procephalic ectoderm primordium
exd is expressed at all stages of development. exd transcripts are present at high levels in early embryos except in the pole cells. Levels decline at gastrulation and then rise during germ band extension. From stage 12 on, transcript levels are modulated with high levels in head and thoracic regions and declining levels in abdominal regions. Levels are moderate in abdominal segments 1 and 2, lower in segments 3 and 4, and lowest in segments 5 and 6. Abdominal segments 7-9 have levels intermeditiate between those of segments 4 and 5. Expression is also observed in the CNS, visceral mesoderm, and somatic mesoderm.
exd is expressed in NB5-6 starting at embryonic stage 11 in abdominal and thoracic lineages, is expressed in all cells in the lineage at stage 13, and is maintained throughout the lineage in subsequent stages. It is also expressed in more anterior NB5-6 lineages.
GBrowse - Visual display of RNA-Seq signals
View Dmel\exd in GBrowse 21-52.4
Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete
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.
polyclonal
Source for identity of: exd CG8933
Source for merge of: exd anon- EST:fe1H3
exd is required for salivary gland formation.
exd mutants show patterning defects in the primary axonal scaffolds of the developing embryonic brain.
The exd gene encodes a product that includes an NLS (nuclear localization signal), an NES (nuclear export signal) and a region required for hth-mediated nuclear localization. The hth gene product is required to overcome the influence of the exd NES (nuclear export signal), possibly by inducing a conformational change in the exd product. The exd and hth gene products interact in the cytoplasm.
The subcellular location of exd gene product and its mammalian counterpart Hsap\PBX1 depends on nuclear export and import signals and is modulated by association with hth protein or its mammalian counterpart Hsap\PKNOX1.
exd function and dpp/wg signalling are antagonistic and divide the leg into two mutually exclusive domains. In the proximal domain exd activity prevents cells from responding to dpp and wg. In the distal domain, exd function is suppressed by the dpp/wg response gene Dll, which prevents the nuclear transport of exd. The division of the limb into two antagonistic domains, as defined by exd function and hh signaling, may be a general feature of limb development.
exd protein localised to the nucleus is proposed to suppress tarsus development and activate arista development. In the mesodermal adepithelial cells of the leg imaginal discs, Scr protein is proposed to be required for the synthesis of a tarsus-inducer that when secreted acts on the ectoderm cells inhibiting nuclear accumulation of exd protein, such that tarsus determination is no longer suppressed and arista determination is no longer activated.
The nucleocytoplasmic localisation of exd protein is highly regulated throughout development.
A 20bp oligonucleotide from the 5' region of Mmus\Hoxb1, a homolog of lab, is sufficient to direct an expression pattern in Drosophila very similar to endogenous lab. This expression requires lab abd exd function. In vitro DNA binding studies reveal that lab requires exd to bind DNA with high affinity.
Clonal analysis establishes a precise boundary for exd requirement along the proximal-distal axis of the leg at the proximal femur; exd is required in proximal, not in distal leg. exd and Dll are required in near complementary domains along the leg, with the exception of the trochanter and proximal femur where both gene functions are needed. exd is expressed in a normal pattern in the absence of hh function.
Mosaic analysis reveals that exd is cell autonomously required and critically involved in adult morphogenesis, not only in the homeotic function, but also in several other developmental processes.
exd is critically involved in adult morphogenesis, not only in the homeotic function, but also in several other developmental processes. In some regions of the adult exd mutant clones exhibit homeotic transformations similar to those produced by known homeotic mutations at Ubx, lab, ss or Antp. In other regions the lack of exd causes novel homeotic transformations producing ectopic eyes and legs. exd is also required for functions not normally associated with homeosis, such as the maintenance of the dorso-ventral pattern in the abdomen, the specification of subpatterns in adult appendages or the arrangement of bristles in the mesonotum and genitalia.
Virtually all of the P{r4/lacZ} expression in Drosophila depends on the same three conserved sequence elements involved in regulating expression in the mouse and lab expression. Expression in the head and the visceral mesoderm requires exd function.
exd is required for the appropriate regulation of at least some of the selector homeodomain proteins downstream target genes.
The exd protein raises the DNA binding specificity of Ubx and abd-A protein, but not that of Abd-B. The exd protein modulates the DNA binding activity of en to a different site. While a region N-terminal of the exd homeodomain is required for Ubx and abd-A cooperativity, en requires a domain C-terminal of the exd homeobox.
Isolated from a Drosophila adult cDNA library, using a fragment containing the human pbx1 homeobox as a probe, under low stringency conditions.
An exd cDNA has been cloned and sequenced, and its expression pattern has been analysed.
Mutations in exd cause homeotic transformations in both the embryo and the adult. The exd gene product acts with the selector homeodomain proteins as a DNA binding transcription factor, thereby altering their regulation of downstream target genes.
exd alters segmental identity without altering the pattern of expression of homeotic genes. It may act by altering the target specificity of these genes.
exd mutants display mesothoracic and metathoracic segments like the prothorax, first abdominal segment is like the posterior abdomen.