serine/threonine kinase - mutants show an inabillity to generate a sufficient number of optic lobe and central brain neurons during postembryonic development - drives the Dacapo dependent cell cycle exit of neurons in the Drosophila brain by promoting and expression
Gene model reviewed during 5.51
Annotated transcripts do not represent all possible combinations of alternative exons and/or alternative promoters.
Low-frequency RNA-Seq exon junction(s) not annotated.
Due to an oversight in the implementation of gene annotation merges, the symbols for some of the transcripts and polypeptides of this gene were changed to non-unique designations in r5.8. Although there were no conflicts within a given release, the same symbols were used for different isoforms in different releases. The affected gene product symbols have now been changed to symbols not used previously in the database; see individual transcript reports for details.
Gene model reviewed during 5.55
5.5, 4.4, 4.2 (northern blot)
None of the polypeptides share 100% sequence identity.
843, 542, 539 (aa); 90, 60, 58 (kD observed); 89, 59.4, 59.1 (kD predicted)
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\mnb using the Feature Mapper tool.
mnb protein is expressed in a subset of neurons in the adult brain, including some symmetrically located neurons, posterior to the antennal lobe. Ten of these neurons co-express sNPF protein. None of the neurons labeled by mnb co-express Scer\GAL4Ilp2.PR.
The 539aa form of mnb is expressed most strongly in larvae and pupae and is the predominant form in third instar larvae.
Higher levels of the 542aa form of mnb protein are observed in embryos and pupae than larvae.
Higher levels of the 843aa form of mnb protein are observed in embryos and pupae than larvae.
mnb protein is most prominent in the mushroom body neuropil and the outer proliferation centers of the optic lobes in the larval brain. In adult brains, the level of mnb protein is low in the optic lobes and central brain hemispheres but is high in retinal pigment cells as well as in the α, β, and γ cells and the peduncle of the mushroom bodies.
GBrowse - Visual display of RNA-Seq signalsView Dmel\mnb 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 merge of: mnb CG7835
Annotations CG7826 and CG7835 merged as CG42273 in release 5.8 of the genome annotation.
Apparently part of 'Sh complex'. Seems to be allelic to Sh, given map position and mnb-associated leg shaking (A. Ferrus and M. Heisenberg, unpublished); yet, Sh mutations do not lead to any grossly aberrant brain morphology and Sh5 plus Sh14 complement mnb1 with regard to anatomical defects caused by the latter (M. Heisenberg, unpublished); mnb1 also complements lethal alleles of 3 genes mapping just distally to Sh alleles (see Tanouye, Lam and Iverson, 1986), i.e., l(1)16Fa, l(1)16Fb and l(1)16Fc; an X-linked enhancer of mnb has been identified, which causes lethality when expressed along with the latter (M. Heisenberg, unpublished); the former maps near cv and (when in combination with mnb1) leads to death late in pupation (mutants can be 'rescued' by opening the pupal case).
When dsRNA constructs are made and transiently transfected into S2 cells in RNAi experiments, an increase in the proportion of S phase cells and/or aneuploidy, an increase in the proportion of G2/M phase cells, an increase in mitotic index and abnormal spindles are seen.
Mutations in mnb cause an abnormal spacing of neuroblasts in the outer proliferation centre of the larval brain. As a consequence the larval brain exhibits a specific and marked reduction of the optic lobes and central brain hemispheres. The insufficient number of distinct neurons in the brain is correlated with specific abnormalities in visual and olfactory behaviour.
In tests of locomotor activity rhythms, singly mutant mnb adults are basically normal, but a high proportion of mnb so double mutants show complex rhythmicities (dual circadian periodicities) with about 20% being arrhythmic (3 times greater than wild type).
Behavioural and anatomical studies demonstrate that central brain lesions can be interpreted behaviourally. Mushroom bodies have normal size and shape. Whole brain is reduced in volume, flies are incapable of olfactory learning.
Brain mass approximately half normal, including smaller than normal optic lobes and reduction in cell number, with the exceptions of the neuropil of the lamina optic ganglion which appears normal in size and the general morphology and peduncle of mushroom body which has apparently normal number of fibers.
Isolation: A mutagenized X provided by J. Merriam.