Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It only takes a minute to sign up.
Sign up to join this community
I am reading a paper and I have come across the following statement:
"Plasmids encoding full-length NCAM140 and NCAM140Δcys, intracellular domain of NCAM140, and the NCAM140ID729–750 fragment were as described".
I know that NCAM140 is an isoform of the NCAM protein with a molecular weight of 140kDa. However, I am not sure what Δcys means in NCAM140Δcys. Any insights are appreciated.
When describing mutations, $\Delta$ usually stands for deleted sequences. In this case it means the exchange of 4 cysteine residues in the NCAM protein by serines to disable palmitoylation and the association of the protein to lipid rafts. If you search for this specific mutation, you will find the paper from Niethammer et al., 2003, which describes the mutation. Figure 2a (below) shows a schematic view of the locus and is described as following in the caption:
Mutation of NCAM140 palmitoylation sites abolishes NCAM140 raft association. (A) Schematic diagram of the structure of NCAM140 and NCAM140Δ. The plasma membrane is indicated by the pair of vertical lines. The semicircles represent the five Ig-like domains. The two fibronectin type III–like domains are shown as black boxes. The expanded segment shows the NH2-terminal sequence of the cytoplasmic domain and the four cysteines that were mutated to serines in the NCAM140Δ construct to remove all sites for palmitoylation.
