Recently, it has been shown that NuMA has a Hook domain and a CC1-Box-like motif, both of which interact with the effector-binding domain of DLIC (Renna et al., 2020). experiments show that cortical dynein performs bulk cytoplasmic transport by gliding microtubules along the cell cortex and through the ring canals to the oocyte. We propose that the dynein-driven microtubule flow could serve as a novel mode of fast cytoplasmic transport. oocyte growth.(A) A cartoon illustration of cytoplasmic dynein and its regulators. The dynein core complex is composed of dimers of dynein heavy chain (orange), dynein intermediate chain (gray), dynein light intermediate chain (blue), and three types of dynein light chains (green). Dynein activity is regulated by the dynactin complex (brown, with p150Glued highlighted in red) and the Lis1-NudE complex (Lis1, yellow; NudE, magenta). A dynein activating adaptor, BicD (purple), is also shown to illustrate the linkage of the dynein complex with a cargo. To note: other cargo adaptors instead of BicD, such as Spindly, HOOK1/3, ninein/ninein- like(NINL), and RAB11 family-interacting protein 3, can be used for dynein activation and cargo recruitment (not shown) (Reck-Peterson et al., 2018). BICDR1 and HOOK3 could recruit two dyneins for increased force and speed (not shown) (Reck-Peterson et al., 2018). (B) Summary of oocyte growth phenotypes in listed genetic background (all with one copy of (#1) is the RNAi line used for all experiments in this study. (C-D) Phalloidin and Orb staining in control (C-C) and (D-D) ovarioles. Oocytes and Orb DS18561882 staining are highlighted with either yellow arrowheads and brackets (C-D and C-D), or with yellow painting (C-D). Scale bars, 50 m. (E) Summary of the Orb staining phenotypes in stage 8 (left) and stage 9 (right) egg chambers in listed genotypes (all with one copy of lines against three listed dynein activating adaptors, BicD, Spindly and Hook (all with one copy of transgene is balanced with a TM6B (Tb) balancer, only non-Tb pupae were selected for this assay. (D-F) Bristle phenotypes in control (D) and in (ECF) male adults. Control and are of the same genotypes as (C). Mild (E) and severe (F) hooked bristle phenotypes are seen in flies. (D-F) Zoom-in images of bristles in the white dashed box in (DCF). Hooked bristles are highlighted with white arrowheads. Dynein has many essential functions during oogenesis. First, it is required for germline cell division and oocyte specification (McGrail and Hays, 1997; Liu et al., 1999). During mid-oogenesis, dynein is required for transport of mRNA ribonucleoproteins (RNPs) and organelles from nurse cells to the oocyte (Mische et al., 2007; Clark et al., 2007; Nicolas Rabbit polyclonal to PCDHGB4 et al., 2009; Lu et al., 2021). Within the oocyte, dynein transports and anchors the anterior and dorsal determinants that are critical for axis determination for future embryos (Januschke et al., 2002; Duncan and Warrior, 2002; Trovisco, 2016). During vitellogenesis, dynein in the oocyte regulates endocytic uptake and maturation of yolk proteins from the neighboring somatic follicle cells (Liu et al., 2015). The oocyte undergoes dramatic cell growth and polarization during DS18561882 oogenesis (Bastock and St Johnston, 2008). Remarkably, the oocyte remains transcriptionally quiescent during most of the oogenesis. For its DS18561882 dramatic growth, the oocyte relies on its interconnected sister cells, nurse cells, for providing mRNAs, proteins, and organelles through intercellular cytoplasmic bridges called ring canals (Bastock and St Johnston, 2008; Mahajan-Miklos and Cooley, 1994). Previously, we showed that dynein heavy chain drives oocyte growth by supplying components to the growing oocyte (Lu et al., 2021). Here, we study the mechanism of dynein-driven transport of cargoes from nurse cells to the oocyte. We find that microtubules, which had previously been considered.