title: Double abdomen induction with low UV-doses inSmittia spec. (Chironomidae, diptera): Sensitive period and complete photoreversibility.
abstract: In embryos of the chironomid midgeSmittia spec., UV-irradiation of anterior pole regions results in double abdomen formation. In this abnormal body pattern, head and thorax are replaced by a mirror image of the abdomen. Irradiation at a particular stage between nuclear migration and blastoderm formation, and with the anterior pole facing the UV-beam, yields 100% double abdomens after a minimum UV-dose (140 J·m-2at 285 nm wavelength). By subsequent exposure to light of longer wavelength, embryos can be reprogrammed so that they develop normally again. The irradiation procedure described is suitable for programming large numbers of embryos for double abdomen formation, with a minimum of side effects and virtually complete photoreversibility.
authors.affiliation: Department of Zoology, University of Texas, 78712, Austin, Texas, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Ripley
authors.affiliation: Department of Zoology, University of Texas, 78712, Austin, Texas, USA.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kalthoff
keywords: Action spectrum; Cytoplasmic RNP-particles; Developmental pathways; Embryonic pattern formation; Morphogenetic determinants