No two different species can share the same niche but can have similar niches,  this is because of competition for resources like food, space etc

Two species cannot coexist permanently in a community if their niches are  identical

TLS Online TPP Program

#Id: 7959

#Unit 2. Cellular Organization

Unfolded-protein response

Key protein –Ire1 promotes formation of Hac1

TLS Online TPP Program

#Id: 7960

#Unit 2. Cellular Organization

Binding of BiP to the luminal domain of monomeric Ire1 prevents formation of the Ire1 dimer.

TLS Online TPP Program

#Id: 7961

#Unit 2. Cellular Organization

Quantity of free BiP in the ER lumen determines the relative proportions of monomeric and dimeric Ire1.

TLS Online TPP Program

#Id: 7962

#Unit 2. Cellular Organization

Hac1 activates transcription of genes encoding several protein-folding catalysts.

TLS Online TPP Program

#Id: 7963

#Unit 2. Cellular Organization

A hereditary form of emphysema illustrates the detrimental effects that can result from misfolding of proteins in the ER.

TLS Online TPP Program

#Id: 7964

#Unit 2. Cellular Organization

Emphysema caused by a point mutation in -antitrypsin, which is normally secreted by hepatocytes and macrophages.