title: A common organization of the T-DNA genes expressed in plant hairy roots induced by different plasmids of Agrobacterium rhizogenes.
abstract: The recently described pathogenic plasmid from Agrobacterium rhizogenes 2659 induces "hairy root" proliferation in infected plants which synthesize a new opine type, provisionally called cucumopine. The T-DNA restriction site map of 2659 differs from other pRi T-DNAs, i.e., mannopine and agropine. However all these three different T-DNAs have a similar organization as detected through hybridization. This, previously shown by our cross-hybridization studies between mannopine and agropine pRi T-DNAs, is here extended to the cucumopine pRi T-DNA; each of the three pRi T-DNA is composed of successive DNA regions that would find actual counterparts in the two other T-DNAs. Equivalence of DNA regions is suggested by their similar length, location and organization in the three T-DNAs and by their sequence homology substantial enough to be reproducibly cross-hybridized in all our experiments. This suggests that the three pRi T-DNAs share most of their functions. This was sought by analysing the pRi 2659 T-DNA gene expression in transformed plant tissues. The mRNA species observed in pRi 2659 carrot hairy roots of in vitro cultures give a pattern that is rather unvariable and resembles those described for some agropine type pRi transformant tissues. This transcript pattern is consistent with the preservation in the pRi 2659 T-DNA of counterparts of most of the open reading frames detected in the TL-DNA of agropine type pRis.
authors.affiliation: Institut de Microbiologie, Université Paris Sud, Bât. 409, 91405, Orsay Cédex, France.
authors.forename: A
authors.initials: A
authors.lastname: Combard
authors.forename: M F
authors.initials: MF
authors.lastname: Baucher