MSL3, MSL, mle3
Gene model reviewed during 5.46
There is only one protein coding transcript and one polypeptide associated with this gene
512, 481 (aa); 58 (kD observed); 57, 53 (kD predicted)
Antibodies were made to regions common to both of the predicted msl-3 proteins.
The putative 481aa msl-3 protein is predicted
from the sequence of one cDNA which represents a transcript generated by
alternative splicing. The encoded protein has three unique amino-terminal
amino acids and is colinear with the longer msl-3 protein from amino
acid 35 of the 512aa protein on. A protein of the expected size has not
been detected in larvae by western blots.
Component of the male-specific lethal (MSL) histone acetyltransferase complex at least composed of mof, msl-1, msl-2 and msl-3.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\msl-3 using the Feature Mapper tool.
msl-3 protein is associated with hundreds of specific sites along the length of the male X chromosome. Variable staining is seen at 10-20 autosomal sites in males. No staining is observed in females. The sites of msl-3 protein staining on the X chromosome colocalize with sites of mle and msl-1 protein staining. Furthermore, the sites of msl-3 protein staining on the autosome are also sites of mle protein staining.
GBrowse - Visual display of RNA-Seq signalsView Dmel\msl-3 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.
Gene products of the male specific lethal (msl) group of genes preferentially associate with the male X chromosome and may have a role in dosage compensation. This may be achieved by regulating an inverse dosage effect, which would be maintained on the male X and nullified on the autosomes.
Gene products of the male specific lethal (msl) group of genes including msl-1, msl-2, msl-3, mle, and mof are associated with all female chromosomes at a low level but are sequestered to the X chromosome in males. There is evidence for the presence of nucleation sites for association of msl proteins with the X chromosome rather than individual gene binding sites.
mof colocalises with the MSL complex on the X chromosome: a sequence of binding events results in the formation of the MSL complex on the X chromosome in males and in the targeting of mof to its presumed site of action.
Male-specific lethal (MSL) proteins accumulate in a subregion of male nuclei (the X chromosome) beginning at late blastoderm stage. X chromosomal binding of the MSLs is observed throughout embryonic and larval development in both diploid and polytene tissues. His4 colocalises with the MSLs in embryos. Binding of the MSLs is interdependent in diploid cells and is prevented in female embryonic cells by Sxl.
Sex- and chromosome-specific binding of the male-specific lethal (msl) proteins occurs in Drosophilid species spanning 4 genera. msl binding correlates with the evolution of the sex chromosomes.
The products of msl-1, msl-2, mle and msl-3 loci specifically associate with hundreds of sites along the X chromosome in males, but not in females. The binding of each of the four proteins requires the functional products from the other three. 2X3A individuals are mosaic for both Sxl expression and msl-1, msl-2, mle and msl-3 binding to the X chromosome, with a perfect inverse correlation at the cellular level between Sxl expression and msl-1, msl-2, mle and msl-3 X chromosome binding.
Immunostaining of embryonic and larval stages demonstrates that His4, msl-1 and msl-3 are associated with the male X chromosome as early as gastrulation, while mle binding is not detected until the late embryonic/late larval stages.
Elements needed for dosage compensation are localised to the X chromosome only after blastoderm and msl-dependent dosage compensation is not necessary during the first part of embryogenesis. This suggest the existance of an additional msl-independent dosage compensation mechanism; dosage compensation of run expression at blastoderm is not dependent on male specific lethal genes.
The four msl gene products interact to form a multiprotein complex.
Mutants are defective for dosage compensation in males. Homozygous males exhibit delayed development; survive as larvae for ten days. Ten-day-old male larvae have small undeveloped imaginal discs, which, however, when transplanted into wild type larvae are capable of undergoing nearly complete (wing, leg) or partial (eye-antenna) differentiation. Mutants show no interaction with mle1. Females transformed into phenotypic males (tra1, tra21) or intersexes (dsx1) are unaffected by msl-31, i.e. msl-31 acts only upon single-X-bearing flies.