Density-dependent factors affect population size in relation to the population’s density.

Density-dependent factors down into two categories. 

Negative density dependence 

Positive density dependence (inverse density dependence

TLS Online TPP Program

#Id: 8618

#XL - T Zoology

Cdc25 phosphatase Activates CDKs in fission yeast

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#Id: 8619

#XL - T Zoology

INK4s

bind to CDK4 and CDK6 monomers, blocking their interaction with cyclin D

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#Id: 8620

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A second class of CKIs found in metazoan cells is the Cip/Kip family of CKIs, consists of three proteins—p21CIP, p27KIP1, and p57KIP2. 

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#Id: 8621

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The Cip/Kip family members bind to cyclin-bound CDKs and block the activity of cyclin D-, E-, A-, and B-containing complexes.

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#Id: 8622

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Cyclins are degraded through the action of two different E3-ligases:

1. SCF (Skp1, Cullin, and F-box proteins) 

2. APC/C or cyclosome

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#Id: 8623

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SCF and APC/C are multisubunit ubiquitin-protein ligases that belong to the RING finger family of ubiquitin-protein ligases.