Lecture 18 - Leaf development Flashcards
What are the three main components of a leaf? [3]
- Petiole
- Blade
- Midvein
True or False? The leaf has a determinate cell fate.
True
True or False? The meristem has a determinate cell fate.
- False
- It has an indeterminate cell fate
What is determined first on a growing primordium?
Adaxial-abaxial patterning
What comes after establishing
Adaxial-abaxial patterning on a growing primordium?
> Blade outgrowth
> Tissue differentiation
What is the role of class I KNOX genes?
- Expressed in meristem
- Help maintain indeterminate growth
What is the role of ARP genes?
- Expressed i n cells of leaf primordia
- Promote determinate growth and differenitation
How can ARP genes affect KNOX-1 genes?
ARPs can act as transcriptional repressors to shut off KNOX-1 genes
How does a leaf acquire adaxial and abaxial polarity?
- Signal from meristem moves into incipient primordium
- Signal conveys adaxial positional informatuon
Name some adaxial specific genes.
- Revoluta
- Phabulosa
- Phavulosa
Name some abaxial specific genes.
- Yabby
- Kanadi
- miR165 & miR166
What does miR165 do?
- Expressed in abaxial side
- Cleaves Phabulosa
What phenotype do GOF phb-1d mutants have?
They have radial, adaxialized leaves
What happens when there is too much kanadi?
The leaf is over abaxialised
What happens when there is too little kanadi?
The leaf is over adaxialised