Differential role of 14-3-3 family members in Xenopus development.
The 14-3-3 proteins are intracellular dimeric phosphoserine/threonine binding molecules that participate in signal transduction, checkpoint control, nutrient sensing, and cell survival pathways. Previous work established that 14-3-3 proteins are required in early Xenopus laevis development by modulating fibroblast growth factor signaling. Although this general requirement for 14-3-3 proteins in Xenopus early embryogenesis is established, there is no information about the specific role of individual 14-3-3 genes. Botanical studies previously demonstrated functional specificity among 14-3-3 genes during plant development. In this study, an antisense morpholino oligo microinjection approach was used to characterize the requirement for six specific 14-3-3 family members in Xenopus embryogenesis. Microinjection experiments followed by Western blot analysis showed that morpholinos reduced specific 14-3-3 protein levels. Embryos lacking specific 14-3-3 isoforms displayed unique phenotypic defects. In particular, reduction of 14-3-3 tau (tau) protein, and to a lesser extent, 14-3-3 epsilon (epsilon), resulted in embryos with prominent gastrulation and axial patterning defects and reduced mesodermal marker gene expression. In contrast, reduction of 14-3-3 zeta (zeta) protein caused no obvious phenotypic abnormalities. Reduction of 14-3-3 gamma (gamma) protein resulted in eye defects without gastrulation abnormalities. Therefore, individual 14-3-3 genes have separable functions in vertebrate embryonic development.
Lau
Jeffrey M C
JM
Center for Cardiovascular Research, Department of Medicine, and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Wu
Chunlai
C
Muslin
Anthony J
AJ
D048948:14-3-3 Proteins / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D019521:Body Patterning; D004625:Embryo, Nonmammalian / Q000196:embryology / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D005123:Eye / Q000196:embryology / Q000378:metabolism; D008648:Mesoderm / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D014981:Xenopus / Q000196:embryology* / Q000378:metabolism
D048948:14-3-3 Proteins; D016376:Oligonucleotides, Antisense; D020033:Protein Isoforms; D012333:RNA, Messenger; D048049:Extracellular Signal-Regulated MAP Kinases