title: The tubulin repertoire of C. elegans sensory neurons and its context-dependent role in process outgrowth.
abstract: Microtubules contribute to many cellular processes, including transport, signaling, and chromosome separation during cell division (Kapitein and Hoogenraad, 2015). They are comprised of αβ-tubulin heterodimers arranged into linear protofilaments and assembled into tubes. Eukaryotes express multiple tubulin isoforms (Gogonea et al., 1999), and there has been a longstanding debate as to whether the isoforms are redundant or perform specialized roles as part of a tubulin code (Fulton and Simpson, 1976). Here, we use the well-characterized touch receptor neurons (TRNs) of Caenorhabditis elegans to investigate this question, through genetic dissection of process outgrowth both in vivo and in vitro With single-cell RNA-seq, we compare transcription profiles for TRNs with those of two other sensory neurons, and present evidence that each sensory neuron expresses a distinct palette of tubulin genes. In the TRNs, we analyze process outgrowth and show that four tubulins (tba-1, tba-2, tbb-1, and tbb-2) function partially or fully redundantly, while two others (mec-7 and mec-12) perform specialized, context-dependent roles. Our findings support a model in which sensory neurons express overlapping subsets of tubulin genes whose functional redundancy varies between cell types and in vivo and in vitro contexts.
authors.affiliation: *Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Dean
authors.initials: D
authors.lastname: Lockhead
authors.affiliation: Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853.
authors.forename: Erich M
authors.initials: EM
authors.lastname: Schwarz
authors.affiliation: Department of Genetics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854.
authors.forename: Robert
authors.initials: R
authors.lastname: O'Hagan
authors.affiliation: Department of Genetics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bellotti
authors.affiliation: *Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Michael
authors.initials: M
authors.lastname: Krieg
authors.affiliation: Department of Genetics, Rutgers, The State University of New Jersey, Piscataway, NJ 08854.
authors.forename: Maureen M
authors.initials: MM
authors.lastname: Barr
authors.affiliation: Department of Chemical Engineering, Stanford University, Stanford, CA 94305 Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Dunn
authors.affiliation: Howard Hughes Medical Institute and Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Sternberg
authors.affiliation: *Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305 mbgoodmn@stanford.edu.
authors.forename: Miriam B
authors.initials: MB
authors.lastname: Goodman