X-Serrate-1 is involved in primary neurogenesis in Xenopus laevis in a complementary manner with X-Delta-1

Dev Genes Evol. 2001 Sep;211(8-9):367-76. doi: 10.1007/s004270100165.


Notch, Delta and Serrate encode transmembrane proteins that function in cell fate specification in the Drosophila melanogaster embryo. Here we report gene expression patterns and functional characterization of a Xenopus Serrate homolog, X-Serrate-1. The isolated cDNA encoded a transmembrane protein with a Delta/Serrate/LAG-2 domain, 16 epidermal growth factor-like repeats and a cysteine-rich region. Expression of X-Serrate-1 was observed ubiquitously from unfertilized egg to tadpole, but an upregulation occurred in the tailbud stage embryo. Adult expression was found in eye, brain, kidney, heart, spleen and ovary. Whole-mount in situ hybridization revealed that the organ-related expression in eye, brain, heart and kidney occurred from an early stage of rudiment formation. Overexpression of X-Serrate-1 led to a reduction of primary neurons, whereas an intracellularly deleted form of X-Serrate-1 increased the number of primary neurons. Although the function of X-Serrate-1 in primary neurogenesis was quite similar to that of X-Delta-1, expression of X-Serrate-1 and X-Delta-1 did not affect each other. Co-injection experiments showed that wild-type X-Serrate-1 and X-Delta-1 suppressed overproduction of primary neurons induced by dominant-negative forms of X-Delta-1 and X-Serrate-1, respectively. These results suggest that X-Serrate-1 regulates the patterning of primary neurons in a complementary manner with X-Delta-1-mediated Notch signaling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Calcium-Binding Proteins
  • Cloning, Molecular
  • Drosophila Proteins
  • Ectoderm / metabolism
  • Gene Expression Regulation, Developmental
  • In Situ Hybridization
  • Intercellular Signaling Peptides and Proteins
  • Intracellular Signaling Peptides and Proteins
  • Jagged-1 Protein
  • Ligands
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Molecular Sequence Data
  • Nervous System / embryology*
  • Nervous System / metabolism
  • Proteins / chemistry
  • Proteins / genetics
  • Proteins / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, Notch
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Serrate-Jagged Proteins
  • Signal Transduction
  • Xenopus Proteins / genetics
  • Xenopus Proteins / metabolism
  • Xenopus laevis / embryology*
  • Xenopus laevis / genetics
  • beta-Galactosidase / metabolism


  • Calcium-Binding Proteins
  • Drosophila Proteins
  • Intercellular Signaling Peptides and Proteins
  • Intracellular Signaling Peptides and Proteins
  • Jagged-1 Protein
  • Ligands
  • Membrane Proteins
  • Proteins
  • RNA, Messenger
  • Receptors, Notch
  • Ser protein, Drosophila
  • Serrate-Jagged Proteins
  • Xenopus Proteins
  • delta protein
  • jag1 protein, Xenopus
  • beta-Galactosidase