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Sekine, S.

Publications and source records attributed to Sekine, S..

2 recordsLinked to original sources

Nanopore formation in the cuticle of the insect olfactory sensillum

Insects sense odorants through small (50-200-nm diameter) pores in the cuticle covering the olfactory sensilla. These nanopores serve as a filter, preventing the entry of larger airborne particles and limiting water loss. Here we show that the nanopores in Drosophila originate from a curved ultrathin film formed in the outermost layer of the cuticle, secreted from specialized plasma membrane protrusions. The gore-tex/Osiris23 gene, encoding an endosomal protein, is required for nanopore formation and odor receptivity, and is expressed specifically in developing olfactory shaft cells. The 24-member Osiris gene family is expressed in various cuticle-secreting cells, and is found only in insect genomes. Some Osiris mutants show defective cuticle-associated functions, suggesting that Osiris genes may provide a platform for investigating functional surface nano-fabrication in insects.\n\nOne Sentence SummaryAn insect-specific endosomal protein promotes the formation of nano-scale pore structures of the apical extracellular matrix.

developmental biology

Improved Split Fluorescent Proteins For Endogenous Protein Labeling

Self-complementing split fluorescent proteins (FPs) have been widely used for protein labeling, visualization of subcellular protein localization, and detection of cell-cell contact. To expand this toolset, we have developed a screening strategy for the direct engineering of self-complementing split FPs. Via this strategy, we have generated a yellow-green split-mNeonGreen21-10/11 that improves the ratio of complemented signal to the background of FP1-10-expressing cells compared to the commonly used split-GFP1-10/11, as well as a 10-fold brighter red-colored split-sfCherry21-10/11. Based on split-sfCherry2, we have engineered a photoactivatable variant that enables single-molecule localization-based super-resolution microscopy. We have demonstrated dual-color endogenous protein tagging with sfCherry211 and GFP11, revealing that endoplasmic reticulum translocon complex Sec61B has reduced abundance in certain peripheral tubules. These new split FPs not only offer multiple colors for imaging interaction networks of endogenous proteins, but also hold the potential to provide orthogonal handles for biochemical isolation of native protein complexes.

bioengineering