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FB2026_02
,
released June 18, 2026
Msp-300, nesprin, Muscle-specific protein 300, jf22
cytoskeletal protein - transports mRNAs from the nucleus to postsynaptic sites during synaptic maturation - controls glutamate receptor density at the neuromuscular junction - promotes myonuclear spacing
Please see the JBrowse view of Dmel\Msp300 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.
Annotated transcripts do not represent all possible combinations of alternative exons and/or alternative promoters.
Low-frequency RNA-Seq exon junction(s) not annotated.
Gene model reviewed during 5.45
~13 (northern blot)
None of the polypeptides share 100% sequence identity.
320, 230 (kD)
300 (kD)
Core component of LINC complexes which are composed of inner nuclear membrane SUN domain-containing proteins coupled to outer nuclear membrane KASH domain-containing nesprins (By similarity). Interacts with klar; this interaction allows the anchoring of the Msp300 nuclear ring structure to the nuclear envelope (PubMed:22927463). Interacts with sls; this interaction mediates the recruitment of Msp300 to the Z-disks (PubMed:22927463).
Msp300 and Klar KASH domains cooperate to mediate the connection between a nuclear ring structure of Msp300 and the plus ends of a unique astral microtubule (MT) network.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Msp300 using the Feature Mapper tool.
The testis specificity index was calculated from modENCODE tissue expression data by Vedelek et al., 2018 to indicate the degree of testis enrichment compared to other tissues. Scores range from -2.52 (underrepresented) to 5.2 (very high testis bias).
Comment: reported as posterior spiracle specific anlage
Msp300 transcripts are expressed throughout development except in pupae. They are most abundant in late embryos.
In myotubes with developed sarcomeric architecture, the protein is localized mainly to the Z discs.
Msp300 protein is initially expressed in a small subset of muscle precursors in each segment at ventral, lateral, and dorsal locations and in visceral muscles. It is expressed by muscle precursors at muscle-ectoderm and muscle-muscle attachment sites. As development continues it becomes associated with the myofibrillar network. Migrating myotubes exhibit high Msp300 levels at their leading edge.
JBrowse - Visual display of RNA-Seq signals
View Dmel\Msp300 in JBrowse2-15
2-17.3
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 JBrowse 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
The complete loss of Msp-300 function does not lead to defects in nuclear positioning in egg chambers.
The KASH domain isoforms of Msp-300 have no essential function for nuclear migration during eye development.
KASH forms of Msp-300 function in egg-laying.
KASH forms of Msp-300 are not required for viability, nor for oogenesis.
Annotations CG31649 and CG33549 merged as CG33715 in release 4.2 of the genome annotation.
dsRNA made from templates generated with primers directed against this gene tested in RNAi screen for effects on Kc167 and S2R+ cell morphology.
snmRNA:128 is derived from the ORF of Msp-300. snmRNA:765 is derived from the ORF of Msp-300.
New annotation (CG31649) in release 3 of the genome annotation. New annotation (CG31916) in release 3 of the genome annotation.
MSP-300 decorates actin filaments and is expressed by muscle precursors at muscle-ectoderm and muscle-muscle attachment sites. As development continues it becomes associated with the muscle myofibrillar network. Migrating myotubes exhibit high MSP-300 levels at their leading edge, but in myotubes with developed sarcomeric architecture the protein is localised mainly to the Z discs.
Source for merge of: Msp-300 CG18251 CG18252
Source for merge of: nesprin BcDNA:GH18470
Source for merge of: Msp-300 nesprin
Source for merge of: CG14035 Msp-300
Source for merge of: Msp-300 CG31916
Source for merge of: nesprin BcDNA:AT10293
Source for merge of: CG31916 BcDNA:LP10936
Source for merge of: CG31916 BcDNA:GH02446
Source for merge of: Msp-300 Bbbf1
Annotations CG14035 and CG33715 merged as CG42768 in release 5.28 of the genome annotation.
Source for identity of nesprin CG31649 was sequence comparison ( date:021108 ).
Isolation of the AF521598 cDNA suggests that "Msp-300" and "nesprin" may represent two parts of a single gene.
Source for merge of nesprin BcDNA:AT10293 was shared cDNA (AT10293) ( date:030530 ).
Source for merge of CG31916 BcDNA:LP10936 was a shared cDNA ( date:030728 ).
Source for merge of CG31916 BcDNA:GH02446 was a shared cDNA ( date:030728 ).
Source for merge of nesprin BcDNA:GH18470 was a shared cDNA ( date:030728 ).
Source for identity of: nesprin CG31649
Source for identity of: Msp300 Msp-300
