Identification of a novel gene involved in asexual organogenesis in the budding ascidian Botryllus schlosseri

Department of Developmental Biology , Stanford University, Stanford, California, United States
Developmental Dynamics (Impact Factor: 2.38). 12/2005; 234(4):997-1005. DOI: 10.1002/dvdy.20583
Source: PubMed


Development via regeneration or budding shares some known genetic pathways with embryogenesis, but no concerted effort has been made to identify genes unique to asexual development. We have identified a novel gene that plays a role in cyclical bud formation and asexual organogenesis in the colonial ascidian Botryllus schlosseri. Athena mRNA is transcribed at high levels during the 24- to 36-hr interval of programmed cell death and new bud initiation at the conclusion of the budding cycle (takeover). Knockdown of Athena by RNAi and antisense morpholinos induced defects in the development of new buds ranging from retardation in growth and abnormal organogenesis to hollow buds lacking organs. As genetic intervention in this organism has not been possible, this study establishes the use of RNAi and morpholinos in Botryllus as well as describing the knockdown phenotype of a new gene.

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Available from: Robert Lauzon, Sep 02, 2014
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    • "Because single zooids, or even pieces of blood vessels, extracted from a colony reconstitute a full colony, experiments employing a large number of animals of identical genetic background can be carried out. Gene function in Botryllus can be inhibited by injection of short interfering RNAs (siRNAs) into the blood vasculature (Laird et al., 2005b). O. dioica is the reference species for appendicularians. "
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    • "The specific primers used to synthesize these siRNAs were as follows: A15 5Ј-AACAAGAG- CAATATCGCGGACCCTGTCTC-3Ј and A13 5Ј-AAGTCCGCGATATT- GCTCTTGCCTGTCTC-3Ј; A25 5Ј- AATGGGATGAAAGACGAGGAGC- CTGTCTC-3Ј and A23 5Ј-AACTC- CTCGTCTTTCATCCCACCTGTCTC-3Ј; A35 5Ј-AAGATTGGAATATAGCTCTC- CCCTGTCTC-3Ј and A33 5Ј-AAG- GAGAGCTATATTCCAATCCCTGTC- TC-3Ј; A55 5Ј-AAATACGACGATAT- ACCAGTGCCTGTCTC-3Ј and A53 5Ј- AACACTGGTATATCGTCGTATCCT- GTCTC-3Ј. An additional set of primers was used to synthesize an unrelated control siRNA (Laird et al., 2005) derived from plasmid sequence: Control5 5Ј-AACCATCTGCTAATCTGTAAC- CCTGTCTC-3Ј and Control3 5Ј-AAGT- TACAGATTAGCAGATGGCCTGTC- TC-3Ј. "
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