The Drosophila Ninein homologue Bsg25D cooperates with Ensconsin in myonuclear positioning

• DOI: 10.1083/jcb.201808176
• Publication Date: 2019-01-09T20:59:11Z
• Authors: Jonathan N. Rosen; Mafalda Azevedo; David B. Soffar; Vitaly P. Boyko; Matthew B. Brendel; Victoria K. Schulman; Mary K. Baylies
• Keywords: Multinucleate; Ectopic expression

Skeletal muscle consists of multinucleated cells in which the myonuclei are evenly spaced throughout cell. In Drosophila, this pattern is established embryonic myotubes, where move via microtubules (MTs) and MT-associated protein Ensconsin (Ens)/MAP7, to achieve their distribution. Ens regulates multiple aspects MT biology, but little known about how itself regulated. We find that physically interacts colocalizes with Bsg25D, Drosophila homologue centrosomal Ninein. Bsg25D loss enhances myonuclear positioning defects embryos sensitized by partial loss. overexpression causes severe immature myotubes fully differentiated myofibers, it forms ectopic organizing centers, disrupts perinuclear arrays, reduces stiffness, decreases larval crawling velocity. These studies define a novel relationship between Bsg25D. At endogenous levels, positively activity during positioning, excess localization organization, disastrous consequences for function.