Phytochromobilin is exported from the plastid to the cytosol where it autocatalytically attaches to the PHY apoprotein through a thioether linkage to a cysteine residue.

TLS Online TPP Program

#Id: 10066

#XL - T Zoology

Extracellular region of a classical cadherin contains five copies of the cadherin domain separated by flexible hinge regions

TLS Online TPP Program

#Id: 10067

#XL - T Zoology

Ca2+ ions bind to sites near each hinge and prevent it

from flexing, so that the whole string of cadherin domains behaves as a rigid and slightly curved rod to generate cell–cell adhesion

TLS Online TPP Program

#Id: 10069

#XL - T Zoology

Each classical cadherin molecule contains: 

A single TM domain

A short C-terminal cytosolic domain

Five extracellular “cadherin” domains (EC1–EC5)

TLS Online TPP Program

#Id: 10070

#XL - T Zoology

Three classes of classical cadherins: 

E-cadherin -present on epithelial cells

N-cadherin - present on nerve, muscle and lens cells

P-cadherin - present on cells in the placenta & epidermis

TLS Online TPP Program

#Id: 10071

#XL - T Zoology

Nonclassical cadherins include proteins:

Protocadherins found in the brain

Desmocollins and desmogleins that form desmosomes

TLS Online TPP Program

#Id: 10072

#XL - T Zoology

Epithelial-to-mesenchymal transition is associated with a reduction in the expression of E-cadherin.