TY - JOUR
T1 - Optimal RNA binding by Egalitarian, a Dynein cargo adaptor, is critical for maintaining oocyte fate in Drosophila
AU - Goldman, Chandler H.
AU - Neiswender, Hannah
AU - Baker, Frederick
AU - Veeranan-Karmegam, Rajalakshmi
AU - Misra, Saurav
AU - Gonsalvez, Graydon B.
N1 - Publisher Copyright:
© 2021 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2021
Y1 - 2021
N2 - The Dynein motor is responsible for the localization of numerous mRNAs within Drosophila oocytes and embryos. The RNA binding protein, Egalitarian (Egl), is thought to link these various RNA cargoes with Dynein. Although numerous studies have shown that Egl is able to specifically associate with these RNAs, the nature of these interactions has remained elusive. Egl contains a central RNA binding domain that shares limited homology with an exonuclease, yet Egl binds to RNA without degrading it. Mutations have been identified within Egl that disrupt its association with its protein interaction partners, BicaudalD (BicD) and Dynein light chain (Dlc), but no mutants have been described that are specifically defective for RNA binding. In this report, we identified a series of positively charged residues within Egl that are required for RNA binding. Using corresponding RNA binding mutants, we demonstrate that specific RNA cargoes are more reliant on maximal Egl RNA biding activity for their correct localization in comparison to others. We also demonstrate that specification and maintenance of oocyte fate requires maximal Egl RNA binding activity. Even a subtle reduction in Egl’s RNA binding activity completely disrupts this process. Our results show that efficient RNA localization at the earliest stages of oogenesis is required for specification of the oocyte and restriction of meiosis to a single cell.
AB - The Dynein motor is responsible for the localization of numerous mRNAs within Drosophila oocytes and embryos. The RNA binding protein, Egalitarian (Egl), is thought to link these various RNA cargoes with Dynein. Although numerous studies have shown that Egl is able to specifically associate with these RNAs, the nature of these interactions has remained elusive. Egl contains a central RNA binding domain that shares limited homology with an exonuclease, yet Egl binds to RNA without degrading it. Mutations have been identified within Egl that disrupt its association with its protein interaction partners, BicaudalD (BicD) and Dynein light chain (Dlc), but no mutants have been described that are specifically defective for RNA binding. In this report, we identified a series of positively charged residues within Egl that are required for RNA binding. Using corresponding RNA binding mutants, we demonstrate that specific RNA cargoes are more reliant on maximal Egl RNA biding activity for their correct localization in comparison to others. We also demonstrate that specification and maintenance of oocyte fate requires maximal Egl RNA binding activity. Even a subtle reduction in Egl’s RNA binding activity completely disrupts this process. Our results show that efficient RNA localization at the earliest stages of oogenesis is required for specification of the oocyte and restriction of meiosis to a single cell.
KW - RNA binding domain
KW - RNA localization
KW - cargo adaptor
KW - cell polarity
KW - molecular motor
UR - http://www.scopus.com/inward/record.url?scp=85105136685&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85105136685&partnerID=8YFLogxK
U2 - 10.1080/15476286.2021.1914422
DO - 10.1080/15476286.2021.1914422
M3 - Article
C2 - 33904382
AN - SCOPUS:85105136685
SN - 1547-6286
VL - 18
SP - 2376
EP - 2389
JO - RNA biology
JF - RNA biology
IS - 12
ER -