Category: Uncategorized

SYMMETRICAL EXPRESSION. "An increasing number of studies from across angiosperms indicate that morphological shifts between radial symmetry and bilateral symmetry are correlated with independent transitions in asymmetric expression of members of the ECE clade of TCP TFs, of which CYCLOIDEA (CYC) was the first characterized member." ( TFs = transcription factors). http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

FLORAL SYMMETRY GENES. "Here we examine the complexity of GRNs by examining one thread of the floral symmetry pathway: TCP and MYB genes and the petal whorl." (GRN = gene regulatory networks). http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

FLORAL SYMMETRY DRIVERS. "In addition to position, changes in morphological characteristics such as symmetry in petal shape, presence or absence of trichomes on petals, colour differences among petals, and changes in cell types on petal surfaces can also lead to shifts in floral symmetry." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

MULTIPLE PETAL FORMS. "In core eudicots this ultimately results in three petal types: a medially positioned abaxial (ventral) petal, two lateral petals and two adaxial (dorsal) petals. Each of these separate groups (two dorsal petals, two lateral petals, and single ventral petal) can vary in multiple morphological characteristics to result in a floral form with a single dorsoventral plane of symmetry." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

RADIAL VERSUS BILATERAL SYMMETRY. "While flower symmetry is generally categorized as radially symmetrical or bilaterally symmetrical, there are clearly many variable traits that make each separate species unique. For example, a shift from radial to bilateral symmetry involving the petal whorl involves a transition from a single petal form within the flower to the individualization of petals within the whorl and the resulting possibility of having multiple petal forms." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

Beautiful dry stone wall. View in LinkedIn

SO ENDS this first of two weekends on the theme of floral symmetry. Symmetry is a pervasive theme in nature, from the quantum to the biological. It is still not clear why symmetry is such a powerful force, so seemingly keenly essential. In the case of flowers, the pollinators could as easily, it seems, have been conditioned on asymmetric flowers. But as we see, plants go to complicated generic solutions to maintain precise symmetric control. View in LinkedIn

SNAPDRAGON MORPHOLOGY. "In A. majus, both paralogues are expressed in the dorsal petals only; however, one copy is more restricted than the other. In other groups, however, the CYC2 expression pattern...has been found. CYC2 genes then activate RAD in the broadest zone of expression. This results in differential expression of DIV, with diffuse expression in dorsal regions and localized epidermal expression in ventral regions. This could result in trichomes developing only in the ventral region." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

GENE DUPLICATION EVENT. "A shift to a bilaterally symmetrical flower generally entails two correlated events: the duplication into two CYC2 paralogues and the dorsal restriction of both paralogues. Additionally, in many groups one paralogue is more dorsally restricted than the other paralogue." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn

DOWNSTREAM CONTROL. "When CYC2 is ubiquitously expressed, then RAD is activated throughout the corolla, which inhibits DIV. DIV remains diffusely expressed throughout the corolla, perhaps not sufficiently to result in the up-regulation of AmMYBL1, leading to the loss of trichomes." http://onlinelibrary.wiley.com/doi/10.1111/nph.13198/full View in LinkedIn