Maternal macho-1 is an intrinsic factor that makes cell response to the same FGF signal differ between mesenchyme and notochord induction in ascidian embryos.
An extracellular signaling molecule acts on several types of cells, evoking characteristic and different responses depending on intrinsic factors in the signal-receiving cells. In ascidian embryos, notochord and mesenchyme are induced in the anterior and posterior margins, respectively, of the vegetal hemisphere by the same FGF signal emanating from endoderm precursors. The difference in the responsiveness depends on the inheritance of the posterior-vegetal egg cytoplasm. We show that macho-1, first identified as a localized muscle determinant, is also required for mesenchyme induction, and that it plays a role in making the cell response differ between notochord and mesenchyme induction. A zygotic event involving snail expression downstream of maternal macho-1 mediates the suppression of notochord induction in mesenchyme precursors.
Kobayashi
Kenji
K
Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8501, Japan. kobaken@ascidian.zool.kyoto-u.ac.jp
Sawada
Kaichiro
K
Yamamoto
Hiroki
H
Wada
Shuichi
S
Saiga
Hidetoshi
H
Nishida
Hiroki
H
D000818:Animals; D001757:Blastomeres / Q000166:cytology / Q000502:physiology; D019521:Body Patterning; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology; D019070:Cell Lineage; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004527:Egg Proteins / Q000235:genetics / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology / Q000502:physiology; D004627:Embryonic Induction; D005346:Fibroblast Growth Factors / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D008648:Mesoderm / Q000166:cytology / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000196:embryology; D009672:Notochord / Q000502:physiology*; D020320:Oligoribonucleotides, Antisense / Q000378:metabolism; D023121:RNA, Messenger, Stored / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014561:Urochordata / Q000196:embryology*
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D004527:Egg Proteins; D047908:Intracellular Signaling Peptides and Proteins; D020320:Oligoribonucleotides, Antisense; D023121:RNA, Messenger, Stored; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; C420970:macho-1 protein, Halocynthia roretzi; D005346:Fibroblast Growth Factors