| A phylloid ground state of reverted floral specimens of Psophocarpus [12/10/2004] |
- Sinopse:
Recombinants of Psophocarpus tetragonolobus (L.) DC (Fabaceae), homozygous for a recessive allele of a master homeotic gene reverted from a normal photosynthetic, sexual reproductive nature to a vegetative, non-reproductive nature. This included transmutative transformation of floral meristems to a non-sexual phylloid floral ground state where the virescent organs maintained their identity but floral meristem identity was cancelled thus giving rise to a form of anachronic reversion. This was usually followed by a scenario of phyllotactic alterations involving the elongation of the floral axis which physically transformed flowers, in varying degrees of spatial permutations by the formation of ancestral floral structures, including gynophore and a pericladial stalk: a form of paleochronic reversion. Research verified that an allele of the master homeotic gene responsible for this phenomenon is a prerequisite to that scenario. Specific permutations are directly controlled by at least four additional homeotic genes recognized, defined and functionally characterized herein. Their qualitative functions (i.e. dominant or recessive) are responsible respectively for the carpel form, being either vascularized (VSCARP) or digonolobe (vscarp); the state of the gynophore being formed (GNF) or nascent (gnf); the state of the pericladial stalk being formed (PCL) or nascent (pcl) and the bracts position remaining parallel (BCT:PRL) at the calyx (or on the pericladial stalk) or being dislocated due to an interbractial stem formation between bracts (bct:prl). Results indicate that floral meristem identity once established can naturally be cancelled with little or no effect on floral organ identity. |
|
Arquivos do artigo (Clique sobre o arquivo para abrir): | |