TY  - JOUR
TI  - Cysteine-rich region of X-Serrate-1 is required for activation of Notch signaling in Xenopus primary neurogenesis.
AU  - Kiyota, Tomomi
AU  - Kinoshita, Tsutomu
T2  - The International Journal of Developmental Biology
AB  - The Notch family genes encode single-pass transmembrane proteins which function in a variety of cell fate specifications in invertebrates and vertebrates. In Xenopus primary neurogenesis, the Notch ligands, X-Delta-1 and X-Serrate-1, mediate Notch signaling and regulate cell differentiation. In the present study, we examined the role of the Serrate-specific cysteine-rich (CR) region in the primary neurogenesis of Xenopus embryos. The ligand constructs containing the DSL (Delta/Serrate/Lag-2) domain in the extracellular region caused a reduction in primary neurons, whereas the DSL-deleted form of X-Delta-1 resulted in the overproduction of primary neurons. However, the DSL-deleted form of X-Serrate-1 or the construct containing only the CR region in the extracellular domain (SerCR) reduced the number of primary neurons. In contrast, the CR-deleted form of X-Serrate-1 (SerACR) lost activity as a Notch ligand, regardless of the presence of the DSL domain within the extracellular domain. Overexpression of X-Delta-1 and X-Serrate-1 strongly induced the expression of Xenopus ESR-1 (XESR-1), a gene related to Drosophila Enhancer of split. SerCR alone also moderately induced the expression of XESR-1, but the SerACR form did not induce this expression. Co-injection of X-Notch-1deltaICD, which deletes the intracellular domain (ICD), with SerCR suppressed a neurogenic phenotype, although co-injection of X-Su(H)1DBM with SerCR did not, indicating that SerCR affects primary neurogenesis through the Notch/Su(H) pathway. These results suggestthatthe CR region of Xenopus Serrate is required for the activation of Notch signaling and cell fate specification in primary neurogenesis.
PY  - 2002
VL  - 46
IS  - 8
SP  - 1057
EP  - 1060
J2  - Int. J. Dev. Biol.
LA  - en
SN  - 0214-6282
SN  - 1696-3547
UR  - https://ijdb.ehu.eus/article/12533029
Y2  - 2024/11/24/13:22:55
ER  -