Class notes
Regulating development in plants
- Course
- Institution
Detailed notes on regulating development in plants
[Show more]
Seller
Follow
7joshlyons7
Content preview
Regulating development inplants
Homeotic mutation has elucidated aspects of plant development
The outstanding model for plant genetics is Arabidopsis thaliana, this was the first plant to
have its genome sequenced, its small, easy to grow in large numbers, can be self or cross
fertilised, it’s a geneticist’s wet dream
Antirrhinum majus(snapdragon) is a plant that has been used for studying the genetics of
floral development, it’s good for comparison with Arabidopsis because Arabidopsis has
radially symmetrical flowers where as antirrhinum has bilaterally symmetrical flowers
Mutants in antirrhinum have been used to identify genes specifying the axes of symmetry in
floral development
Ariel parts of plant develop from the shoot apical meristem
The meristem is continually mitotically active, during cell divisions continually renew the
apex which show intermediate growth.
Cells around the meristem differentiate to produce leaf primordia
Leaf primordia shows determinate growth= they won’t produce any further structures
Flowering in plants occurs as a result of a change in the commitment of cells in the root
meristem, from vegetative to reproductive structures. Usually triggered by environmental
stimuli
If the shoot terminates then the meristem Is reprogrammed to become a floral meristem
Floral meristems are determinate, they generate floral primordia that represents the
terminal differentiation
Mutation in snapdragon call floricaula cause a homoeotic transformation in the meristem
resulting in highly branched and complex inflorescences that don’t produce determinate
flowers
The homologous gene in Arabidopsis mutates to give the same phenotype called “leafy”
The leafy/floricaula gene encodes a transcription factor that’s need to initiate the expression
of the gene responsible for floral development, so when not, functional can’t produce floral
organs
How are floral organs specified?
established as a result of the interpretation of positional information in the shoot tip
flowers comprise 4 concentric whorls of organs: whorl 1- sepals, whorl 2- petals, whorl 3-
stamens and whorl 4- carpel (female structures)
3 classes of mutation change the fate of an adjacent pair of whorls
Class A: mutation results in the replacement of sepals and petals by carpels and stamens
Class B: mutation results in replacement of petals and stamens by sepals and carpels
Class C: mutation results in loss of stamens and carpels, and the formation of extra whorls of
sepals and petals
Based on these phenotypes it was possible to develop a model for how genetic
determination of floral anatomy was achieved= ABC model
Rules of ABC model:
1. There are 3 classes of homeotic gene, A, B and C
2. Each class expressed in 2 adjacent whirls of the floral meristem
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller 7joshlyons7. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $3.86. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
52355 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now