Gene Wednesday: LALBA

Righto!  Here's post number six, and guess what.... six people signed up to follow this little blog. Talk about motivating factors.

Today is the inaugural Gene Wednesday.  I love genes.  I love genetics.  So here's where I'll spotlight one gene.  I promise, all these posts this week, though they seem disjointed, are leading to something.

Today's gene is LALBA. It codes for the protein human alpha-lactalbumin.  It's located on human chromosome 12q13 (the long arm of chromosome 12).  As you can probably guess by the name, it's the principle protein in milk.  But it's oh so much more.  It binds to to another protein, lactose synthase, and makes lactose, the principle sugar found in milk.  LALBA is only expressed in mammary tissue, and is hormonally regulated.  It is highly conserved among mammals, and mice that have both copies of LALBA deleted make a thick milk lacking lactose that does not sustain the pups, showing that LALBA is involved in lactose synthesis and that lactose is necessary for sustaining infants.



Alpha-lactalbumin appears to do much more than make lactose.  It can bind together into a multimeric protein that has apoptotic properties - it can help kill tumor-like cells but not normal cells in culture.   Some data suggest it also has microbicidal activity And recently, a protein dubbed HAMLET (human alpha-lactalbumin made lethal to tumor cells) is alpha-lactalbumin folded in a different way when exposed to acidic environments that, as the somewhat awkward name suggests, appears to specifically kill tumor cells. So one gene, one protein, lots of different functions.  Neat!