RAB11A and RAB11B control mitotic spindle function in intestinal epithelial progenitor cells

• Published in: EMBO reports 2023-09, Vol.24 (9), p.e56240-e56240
• Main Authors: Joseph, Ivor, Flores, Juan, Farrell, Victoria, Davis, Justin, Bianchi‐Smak, Jared, Feng, Qiang, Goswami, Sayantani, Lin, Xiang, Wei, Zhi, Tong, Kevin, Feng, Zhaohui, Verzi, Michael P, Bonder, Edward M, Goldenring, James R, Gao, Nan
• Format: Article
• Language: English
• Subjects: Ablation; Animal models; Animals; Apoptosis; Cell cycle; Cell death; Cell division; Cell self-renewal; Cells (biology); Defects; EMBO05; EMBO06; EMBO34; Endosomes; Epithelial cells; Epithelium; Gene deletion; Homeostasis; Intestine; Isoforms; Kinesin; Lethality; Life Sciences; Mammals; Mammals - metabolism; Mice; Microtubules; Mitosis; Progenitor cells; Protein turnover; Proteomics; rab GTP-Binding Proteins - metabolism; Spindle Apparatus - metabolism; Spindles; Stem Cells - metabolism
• ISSN: 1469-221X; 1469-3178
• DOI: 10.15252/embr.202256240

RAB11 small GTPases and associated recycling endosome have been localized to mitotic spindles and implicated in regulating mitosis. However, the physiological significance of such regulation has not been observed in mammalian tissues. We have used newly engineered mouse models to investigate intestinal epithelial renewal in the absence of single or double isoforms of RAB11 family members: Rab11a and Rab11b. Comparing with single knockouts, mice with compound ablation demonstrate a defective cell cycle entry and robust mitotic arrest followed by apoptosis, leading to a total penetrance of lethality within 3 days of gene ablation. Upon Rab11 deletion ex vivo , enteroids show abnormal mitotic spindle formation and cell death. Untargeted proteomic profiling of Rab11a and Rab11b immunoprecipitates has uncovered a shared interactome containing mitotic spindle microtubule regulators. Disrupting Rab11 alters kinesin motor KIF11 function and impairs bipolar spindle formation and cell division. These data demonstrate that RAB11A and RAB11B redundantly control mitotic spindle function and intestinal progenitor cell division, a mechanism that may be utilized to govern the homeostasis and renewal of other mammalian tissues. Synopsis Double knockout of the small GTPases Rab11a and Rab11b in mouse intestinal epithelia leads to mitotic spindle defects in dividing gut progenitor cells, cell cycle arrest and apoptosis, impairing tissue renewal. Induced genetic ablation of Rab11a and Rab11b in mouse intestinal epithelial cells (IECs) cause 100% lethality within 3 days. IECs lacking Rab11a and Rab11b exhibit mitotic spindle defects, cell cycle arrest, and apoptosis. RAB11A and RAB11B interact with mitotic spindle regulatory protein networks including the KIF11 machinery. Graphical Abstract Double knockout of the small GTPases Rab11a and Rab11b in mouse intestinal epithelia leads to mitotic spindle defects in dividing gut progenitor cells, cell cycle arrest and apoptosis, impairing tissue renewal.