Methods for determining gene function Study the effects of disrupting gene function (ap3 mutants) Examine the expression of the gene (GUS, In situ)
Methods for examining the expression of a gene Reporter construct (AP1::GUS) Pros: Easy, sensitive, can be used to define promoter region. Cons: Indirect, only tells you where the promoter sequences you’ve selected express the fused GUS reporter. This does not necessarily correspond to the actual expression pattern of the gene of interest. It also requires transgenic plants.
In Situ Hybridization Molecular technique that allows one to detect localization of mRNA in a tissue Pros: -Represents the best estimate of the actual expression pattern of a gene -Does not require the production of transgenic plants Cons: -Can be technically challenging -The expression of some genes is difficult to detect -Cannot be used to determine promoter region
An example of AGAMOUS expression the an inflorescence
SEEDSTICK::GUS is expressed in carpels
SEEDSTICK::GUS is expressed in ovules
AP1 RNA is expressed in flower meristems FM SAMFM
AP1::GUS is expressed in flower meristems
AG RNA is expressed in cells that will form stamens and carpels petal sepal carpel leaf sepal stamen
FUL::GUS is expressed in valves
FRUITFULL RNA accumulates in valves valve
FRUITFULL RNA accumulates in valves valvereplum
IND::GUS is positively regulated by SHATTERPROOF wild typeshatterproof replum valve