Unassembled or misfolded proteins in the ER are often transported back to the cytosol, where they are degraded in the ubiquitin-proteasome pathway

TLS Online TPP Program

#Id: 1834

#Unit 11. Evolution and Behavior

Permian- Major mass extinctions, amphibians decline

TLS Online TPP Program

#Id: 7075

#Unit 3. Fundamental Processes

isoleucyl-tRNA synthetase has a nearby editing pocket (a deep cleft in the enzyme) that allows it to proofread the product of the adenylylation reaction. AMP-valine (as well as adenylylates of other small amino acids, such as alanine) can fit into this editing pocket, where it is hydrolyzed and released as free valine and AMP. In contrast, AMP-isoleucine is too large to enter the editing pocket and is therefore not subject to hydrolysis. As a consequence, isoleucyl-tRNA synthetase discriminates against valine twice: in the initial binding and adenylylation of the amino acid (discriminating by a factor of 100), and then in the editing of the adenylylated amino acid (again discriminating by a factor of 100), for an

overall selectivity of 10,000-fold (i.e., an error rate of 0.01%).

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#Id: 5961

#Unit 10. Ecological Principles

TLS Online TPP Program

#Id: 3218

#Unit 4. Cell Communication and Cell Signaling

Chemical carcinogens classified into two general categories:
1. Direct-acting carcinogens
2. Indirect-acting carcinogens

TLS Online TPP Program

#Id: 1616

#Unit 4. Cell Communication and Cell Signaling

Humans CLRs that function as PRRs, most of which recognize one or more specific sugar moieties such as mannose (e.g., the mannose receptor and DC-SIGN), fucose (e.g., Dectin-2 and DC-SIGN), and glucans (e.g., Dectin-1).