March 10, 2022

Talk by Adam Norris

• Alternative splicing and Post-transcriptional regulation have issues with scRNA-seq

• Enormous diversity comes from Alternative splicing

  • DScam in drosphila has 38k isoforms (There's only 20k genes in their genome)

• Workflow is:

  • Define the isoforms

  • ?

  • Find the functional significance (This is the hard part)

Touch Neurons

• Neurons at the either end of the worm that when touched cause the worm to reverse direction

• mec-8 is the splicing regulator of mec-2?

• They compared the function of mec-2 mutates to WT touch neurons

• Did scRNA-seq on cells they sorted out using FACS that were specifically the touch neurons, and call it cell-specific RNA-seq

• mec-2 has an alternative c-terminus bases on mec-8 regulation

• Without mec-8 there's an extra mec-2 exon

• Question: "Is mec-2 important for mechanosensation and chemosensation?"

• They edited with CRISPR to force the short and long isoform

  • Found the short isoform(alone) doesn't work with touch

  • Long and short work in olfactory

  • mec-8 rescue saves the phenotype

Elephant in the room

• They missed a huge mec-2 exon

• They then did the CRISPR edits with the long and extra-long isoforms and found both were needed

  • Indicates intergenic complementation

  • Possible heterodimer/multimer