#dephosphorylation

Gene Cloning Process

Why is alkaline phosphatase used in cloning?

DNA ligase catalyzes phosphodiester bond formation only between adjacent 3' hydroxyl and 5' phosphate termini. Vector linearized with single restriction enzyme retains complementary sticky ends bearing 5' phosphates, readily self-ligating and producing high background of empty clones. Alkaline phosphatase, including calf intestinal or shrimp isoforms, hydrolyzes 5' phosphate groups leaving 5' hydroxyl termini, rendering the vector ligation-incompetent unless paired with phosphorylated insert DNA supplying phosphates. Subsequent ligation yields circular recombinant product with one nick at each junction, later repaired after transformation into host bacteria.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

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Cell Signaling ELR Pathways - I

SHP1-mediated regulation of cytokine signaling is

short-term and reversible, is consistent with established principles of cell signaling, receptor pharmacology and cellular regulation. Experimental measurements of binding parameters, genetic loss-of-function studies and pharmacological interventions all converge on the same interpretation. Related options address neighboring concepts but do not satisfy the precise criterion stated in the question.

Ref: NCERT Biology Class 11–12 Alberts et al Molecular Biology of the Cell Lodish et al, Molecular Cell Biology Cooper & Hausman, The Cell Abbas et al., Cellular and Molecular Immunology (for immunology sections)

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Cell Signaling GPCR Pathways - I

Protein phosphatase action on CaM-Kinase II causes

enzyme inactivation, is consistent with established principles of cell signaling, receptor pharmacology and cellular regulation. Experimental measurements of binding parameters, genetic loss-of-function studies and pharmacological interventions all converge on the same interpretation. Related options address neighboring concepts but do not satisfy the precise criterion stated in the question.

Ref: NCERT Biology Class 11–12 Alberts et al Molecular Biology of the Cell Lodish et al, Molecular Cell Biology Cooper & Hausman, The Cell Abbas et al., Cellular and Molecular Immunology (for immunology sections)

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Brassinosteriod

Dephosphorylation of BIN2 is mediated by:

That points to B: BSU1. Compared with the other options, BSU1 is the one that correctly describes the Brassinosteriod concept. The wrong ones are A) PP2A; C) CDG1; D) BAK1. If you’re stuck, eliminate anything that contradicts a basic fact you already know for this topic.

Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.

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