Original antigenic sin

Tendency to focus an immune attack on those structures that were present during the original.

This means that our immune systems effectively ignore the subtle changes occurring each year in pathogens

TLS Online TPP Program

#Id: 9840

#XL - R Botany

Plant phytochrome is an autophosphorylating

serine/threonine kinase that may phosphorylate

other proteins

TLS Online TPP Program

#Id: 9841

#XL - R Botany

Three distinct classes of photoreceptors mediate the effects of UV-A/blue light (320–500 nm): the cryptochromes, phototropins and the ZEITLUPE (ZTL) family of proteins

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#Id: 9842

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Cryptochromes under blue light causes

1.Suppression of hypocotyl elongation

2.Promotion of cotyledon expansion

3.Membrane depolarization

4.Inhibition of petiole elongation

5.Anthocyanin production

6.Circadian clock entrainment

TLS Online TPP Program

#Id: 9843

#XL - R Botany

The HY4 gene encodes a 75-kDa cry1 protein with significant sequence homology to microbial DNA photolyase

TLS Online TPP Program

#Id: 9844

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Cryptochromes bind a (FAD) and the pterin 5,10 methyltetrahydrofolate (MTHF) as chromophores

TLS Online TPP Program

#Id: 9845

#XL - R Botany

cry2 protein is preferentially degraded under blue light, whereas cry1 is much more stable.