The two key components in protein targeting in ER:

Signal recognition particle (SRP)

SRP receptor

#Id: 2245

#Section 3: Genetics, Cellular and Molecular Biology

#Id: 2246

#Section 3: Genetics, Cellular and Molecular Biology

Some people have an allele called Δ32 at the CCR5 locus in which 32 bp are deleted.

CCR5 that plays a role in inflammatory response. Unfortunately, this protein is also a key to human immunodeficiency virus (HIV) infection. The virus binds to a loop of the CCR5 protein and then enters the cell.

The missing part of the gene codes for the loop in the protein to which the virus attaches. 

#Id: 8972

#Section 3: Genetics, Cellular and Molecular Biology

#Id: 8973

#Section 3: Genetics, Cellular and Molecular Biology

The current record holder is the gene Dscam in Drosophila. Alternative splicing of its 95 exons could potentially produce more than 38,000 kinds of proteins from this single gene.

#Id: 8974

#Section 3: Genetics, Cellular and Molecular Biology

#Id: 2249

#Section 3: Genetics, Cellular and Molecular Biology

Chromosome Evolution

Fissions and fusion is the most common way for the number of chromosomes to change.

Humans have 23 pairs of chromosomes, but all of the other great apes have 24 pairs. At some point since our lineage split from that of chimpanzees, two chromosomes fused