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A. lfy flower
B. lfy inflorescence

Mutations in the LEAFY flower meristem identity gene generally cause a partial to complete transformation of flowers into shoots. The severity of this phenotype varies along the inflorescence such that the basal flowers are completely transformed into shoots, whereas the apical flowers display only a partial transformation. Related Links

LFY (Weigel lab)

These later-arising lfy mutant flowers generally lack petals and stamens, and largely consist of leaf-, sepal-, and carpel-like organs. This is consistent with molecular and genetic data which show that LFY plays a major role in the up-regulation of the B-function organ identity genes, and this role of LFY is mediated in part through its interactions with the UNUSUAL FLORAL ORGANS gene. Consistent with the loss-of-function phenotype, constitutive expression of LFY from the CaMV35S promoter leads to a conversion of shoots into flowers, indicating that LFY is sufficient to specify flower meristem identity. The LFY protein binds DNA in vitro, and appears to function as a novel type of transcriptional regulator. Although LFY RNA accumulates at low levels during vegetative development, LFY expression is significantly up-regulated in emerging flower primordia.
Selected References:

Coen, E.S., Romero, J.M., Doyle, S., Elliot, R., Murphy, G., and Carpenter, R. (1990). FLORICAULA : homeotic gene required for flower development in Antirrhinum majus. Cell 63, 1311-1322.

Huala, E., and Sussex, I.M. (1992). LEAFY interacts with floral homeotic genes to regulate Arabidopsis floral development. The Plant Cell 4, 901-913.

Lee, I., Wolfe, D.S., Nilsson, O., and Weigel, D. (1997) A LEAFY co-regulator encoded by UNUSUAL FLORAL ORGANS. Current Biol. 7:95-104.

Weigel, D., Alvarez, J., Smyth, D.R., Yanofsky, M.F., and Meyerowitz, E.M. (1992). LEAFY controls floral meristem identity in Arabidopsis. Cell 69, 843-859.

Weigel, D. and Meyerowitz, E.M. (1993). Activation of floral homeotic genes in Arabidopsis. Science, 261:1723-1726.

Weigel D, Nilsson O: A developmental switch sufficient for flower initiation in diverse plants. Nature 1995, 377:495--500.