Secondary growth in monocotyledons

Due to lack of cambium in monocotyledons, secondary growth is absent. But Very few plants in monocots shows anomalous secondary growth such as Dracaena, Yucca, Aloe, Sansevieria and Agave

TLS Online TPP Program

#Id: 8613

#XL - T Zoology

Threonine -160 phosphorylation is mediated by 

CDK-activating kinase (CAK)

TLS Online TPP Program

#Id: 8614

#XL - T Zoology

Two inhibitory phosphorylations on CDK play a critical role in controlling CDK activity:

Y15

T14

TLS Online TPP Program

#Id: 8615

#XL - T Zoology

Y15 & T14 are situated in the G-loop of the CDK, containing the consensus sequence GEGT14Y15GVV

TLS Online TPP Program

#Id: 8616

#XL - T Zoology

Phosphorylation of T14 and Y15 in this G-loop

introduces negative charge that electrostatically interferes with the binding of ATP in the catalytic pocket.

TLS Online TPP Program

#Id: 8617

#XL - T Zoology

Wee1 kinase Inhibits CDKs in all organisms

TLS Online TPP Program

#Id: 8618

#XL - T Zoology

Cdc25 phosphatase Activates CDKs in fission yeast