Evolution of insect development: to the hemimetabolous paradigm.
Mechanisms of insect development have been extensively studied in Drosophila melanogaster, a holometabolous insect. However, recent studies on other insects have gradually revealed that there exist new developmental paradigms. In this review, we focus on the new hemimetabolous paradigm. We highlight how hemimetabolous short-germ or intermediate-germ embryos establish the anterior/posterior (A/P) pattern and the importance of dynamic cell movement during germband formation. In hemimetabolous insects, orthodenticle, encoding a homeodomain-containing transcription factor, and wingless/Wnt signaling could play crucial roles in the A/P pattern formation. We also discuss recent evidence suggesting that insect developmental modes may have evolved by heterochronic shifts, while retaining certain universal metazoan features.
Mito
Taro
T
Department of Life Systems, Institute of Technology and Science, University of Tokushima, Minami-Jyosanjima-cho, Tokushima City, Japan. mito@bio.tokusima-u.ac.jp
Nakamura
Taro
T
Noji
Sumihare
S
D000818:Animals; D005075:Biological Evolution; D019521:Body Patterning / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology; D019476:Insect Proteins / Q000235:genetics* / Q000502:physiology; D007313:Insecta / Q000166:cytology / Q000196:embryology / Q000235:genetics*; D008675:Metamorphosis, Biological / Q000235:genetics; D015398:Signal Transduction; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism / Q000502:physiology
D018398:Homeodomain Proteins; D019476:Insect Proteins; D051153:Wnt Proteins; D051176:beta Catenin