Caenorhabditis elegans sqt‐3 mutants have mutations in the col‐1 collagen gene

Abstract

sqt‐3 mutants of Caenorhabditis elegans form dumpy larvae and adults and display allele‐specific defects in locomotion, fertility, and viability. We have determined that the sqt‐3 locus encodes COL‐1 collagen. We physically mapped the col‐1 gene to a cosmid on chromosome V whose position is consistent with the location of the sqt‐3 gene. We also observed morphological defects in sqt‐3 mutants at stages that correlate with the mRNA expression patterns of col‐1. Sequence analysis of the col‐1 gene in the three temperature‐sensitive mutants revealed that each allele of sqt‐3 has a unique missense mutation causing arginine or glutamic acid to replace glycine in a Gly‐X‐Y triple helical domain. These glycine substitutions may result in longer non‐collagenous domains, which may decrease the thermal stability or impart additional flexibility to mutant trimers. In addition, we describe four corrections to the published sequence of col‐1, including one fifteen nucleotide addition that completes a conserved domain in the amino terminal coding region. © 1994 Wiley‐Liss, Inc. Copyright © 1994 Wiley‐Liss, Inc.