Muscular exophers contain organelles and large protein complexes. Arrows: white—exopher, blue—muscle cell, green—mitochondria, red—proteasome foci. MOM—mitochondrial outer membrane.
BWM actively releases significant amounts of exophers. The image shows the middle part of the worm's body with muscles marked with dashed lines. Arrows indicate representative exophers, and the asterisk indicates the position of the vulva.
The ultrastructure of the muscular exopher and its schematic view. Arrows: red—morphologically changed mitochondria inside the exopher, yellow—normal, elongated mitochondria inside the muscle cell. c—cuticle, m—muscle, e—exopher.
Comparison between muscular exopher and coelomocyte. Arrows: white—exopher, blue—muscle, green—coelomocyte.
Exophers are formed via a pinching‐off mechanism. Arrows: white—exopher, blue—muscle cell, red—distorted muscle cell membrane during exopher formation.
Production of muscular exophers is not evenly distributed across all muscle cells. The highest number of exophers is produced by the muscles adjacent to the vulva. n = 46; N = 3.
Exophers may remain connected to the sending BWM cells via thin elastic tubes that allow further transfer of cellular material. Arrows: white—exopher, blue—muscle cell, red—cellular material transferred to exopher via elastic tube.
Knockdown of two autophagy genes, atg‐7 and lgg‐1 significantly reduces the number of generated exophers. n = 91–103; N = 3.
Proteostasis disruption by hsf‐1 knockdown does not increase exopher production. n = 60 and 55; N = 2.
Challenging proteostasis via oxidative stress but not heat stress increases exophers production. n = 30; N = 3.