To end, my favorite experiment from this paper. Poly(A)-binding protein (Pab1) puncta are readily visible in many filamentous fungi, but when we tagged the Pab1 ortholog in A. nidulans we could not see them. Using FRAP, we found they were obscured by a bright cytosolic signal! [7/7]
Endosomal hitchhiking and NDR kinase signaling coordinate SsdA-mRNP localization https://www.biorxiv.org/content/10.64898/2026.04.14.718127v1
The Reck-Peterson lab at Weill Cornell Medicine is seeking a technician or staff scientist to work on Aspergillus projects. Broad background in fungal biology and techniques required. Bioinformatics skills preferred. Find out more at: reckpetersonlab.org.
Thanks to my supervisors @ewjwallace.bsky.social and Ken Sawin for their support throughout my PhD! [6/7]
SsdA shares strong sequence similarity with S. cerevisiae Ssd1, a translational repressor. This raises the interesting possibility that SsdA puncta represent translationally repressed mRNPs, dissolved near tips to allow local regulation of translation during polarized growth. [5/7]
SsdA puncta are largely depleted near hyphal tips, despite early endosomes being abundant in the same region. We found that the extent of this depletion correlates with hyphal growth rate. [3/7]
This tip-proximal depletion depends on NDR kinase CotA. Acute inhibition of an analog-sensitive CotA allele causes SsdA puncta to accumulate near tips. A nonphosphorylatable SsdA mutant shows the same phenotype. [4/7]
SsdA puncta hitchhike on early endosomes via PxdA and DipA, adaptors previously characterized for peroxisome hitchhiking. This raises the possibility that they serve as a adaptors for different types of cargo. (SsdA in magenta and early endosomes in green) [2/7]
Happy to share that the bulk of my PhD work is now on bioRxiv! We followed SsdA, the A. nidulans ortholog of yeast RNA-binding protein Ssd1, and found it forms motile mRNP puncta in hyphae. [1/7] www.biorxiv.org/content/10.6...
