Phosphorylation of Pnut in the Early Stages ofDrosophilaEmbryo Development Affects Association of the Septin Complex with the Membrane and Is Important for Viability

Abstract

Septin proteins are polymerizing GTPases that are found in most eukaryotic species. Septins are important for cytokinesis and participate in many processes involving spatial modifications of the cell cortex. In Drosophila, septin proteins Pnut, Sep1, and Sep2 form a hexameric septin complex. Here, we found that septin protein Pnut is phosphorylated during the first 2 hr of Drosophila embryo development. To study the effect of Pnut phosphorylation in a live organism, we created a new Drosophila pnut null mutant that allows for the analysis of Pnut mutations during embryogenesis. To understand the functional significance of Pnut phosphorylation, Drosophila strains carrying nonphosphorylatable and phospho-mimetic mutant pnut transgenes were established. The expression of the nonphosphorylatable Pnut protein resulted in semilethality and abnormal protein localization, whereas the expression of the phospho-mimetic mutant form of Pnut disrupted the assembly of a functional septin complex and septin filament formation in vitro. Overall, our findings indicate that the controlled phosphorylation of Pnut plays an important role in regulating septin complex functions during organism development.

Comparison of Drosophila melanogaster Embryo and Adult Proteome by SWATH-MS Reveals Differential Regulation of Protein Synthesis, Degradation Machinery, and Metabolism Modules

“…This suggests that PTMs do not appear to vary much between the two developmental stages, although we realize this conclusion is only applicable in the cases of the most abundant proteins and at the level of the whole animal. Regulation of PTMs proteins in particular organs, at specific stages of development and for low abundant proteins, such as transcription factors, is surely of crucial importance for the development of an organism. , …”

“…Regulation of PTMs proteins in particular organs, at specific stages of development and for low abundant proteins, such as transcription factors, is surely of crucial importance for the development of an organism. 47,48 ■ ASSOCIATED CONTENT * S Supporting Information…”

Septins regulate border cell shape and surface geometry downstream of Rho

“…Septins assemble into heteromeric complexes in many contexts (Dolat et. al, 2014;Woods and Gladfelter, 2020), and loss of a single septin can lead to destabilization of the complex (Menon and Gaestel, 2015; Akhmetova et. al, 2018;Xu et.…”

“…We used this to define the surface of the border cell cluster, and exported this file as a .h5 file. This .h5 file was imported into meshlab (2) to clean up the mesh as well as generate a file that can be analyzed using ImSAnE (Image Surface Analysis Environment) (6). Meshlab version used was MeshLab_64bit v1.3.3.…”

Determinantes estruturais para a especificidade de interação nas interfaces G e NC de septinas: validando as regras de substituição na montagem do filamento

“…De longe, as septinas de levedura e septinas humanas são as mais bem estudadas. [6][7] Porém, estudos em septinas de outros organismos estão começando a ter maior ênfase, destacando septinas de: fungos fitopatogênicos [8][9][10] , Caenorhabditis elegans [11][12] , Schistosoma mansoni 13,14, , Drosophila melanogaster [15][16] e Mus musculus. [17][18] Figura 2 -Distribuição filogenética de septinas nos organismos eucariotos.…”