The C elegans hunchback homolog, hbl-1, controls temporal patterning and is a probable microRNA target

Dev Cell. 2003 May;4(5):639-50. doi: 10.1016/s1534-5807(03)00124-2.


hunchback regulates the temporal identity of neuroblasts in Drosophila. Here we show that hbl-1, the C. elegans hunchback ortholog, also controls temporal patterning. Furthermore, hbl-1 is a probable target of microRNA regulation through its 3'UTR. hbl-1 loss-of-function causes the precocious expression of adult seam cell fates. This phenotype is similar to loss-of-function of lin-41, a known target of the let-7 microRNA. Like lin-41 mutations, hbl-1 loss-of-function partially suppresses a let-7 mutation. The hbl-1 3'UTR is both necessary and sufficient to downregulate a reporter gene during development, and the let-7 and lin-4 microRNAs are both required for HBL-1/GFP downregulation. Multiple elements in the hbl-1 3'UTR show complementarity to regulatory microRNAs, suggesting that microRNAs directly control hbl-1. MicroRNAs may likewise function to regulate Drosophila hunchback during temporal patterning of the nervous system.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3' Untranslated Regions / genetics
  • 3' Untranslated Regions / metabolism
  • Alleles
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Body Patterning*
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / genetics*
  • Caenorhabditis elegans Proteins / metabolism*
  • Cell Lineage
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism*
  • Down-Regulation
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / metabolism*
  • Exons
  • Gene Expression Regulation, Developmental
  • Introns
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Molecular Sequence Data
  • Mutation
  • RNA Interference
  • Repressor Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Time Factors
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism*


  • 3' Untranslated Regions
  • Caenorhabditis elegans Proteins
  • DNA-Binding Proteins
  • Drosophila Proteins
  • LIN-29 protein, C elegans
  • MicroRNAs
  • Repressor Proteins
  • Transcription Factors
  • hb protein, Drosophila
  • hbl-1protein, C elegans
  • lin-4 microRNA, C elegans