Biology Reference
In-Depth Information
MBP Ligands and Functions
On the other hand, when looking to its capability to bind a number of
different ligands (Campagnoni, Skoff, 2001), MBP appears to be a good
candidate as an IUP. MBP can bind many divalent cations, in particular
zinc, a physiological ligand present in myelin (Earl
et al
., 1991;
Cavatorta
et al
., 1994; Riccio
et al
., 1995; Tsang
et al
., 1997). MBP can
also bind small molecules such as the heme group (Vacher
et al
., 1984;
Morris
et al
., 1987); azo compounds (Liebes
et al
., 1976); serotonin and
hallucinogens (Alivisatos
et al
., 1971; Carnegie
et al
., 1972) and GTP
(Chan
et al
., 1988).
Binding of MBP to detergent and lipids has been studied in depth,
although MBP was considered to be an extrinsic, lipid-free and water-
soluble protein (Riccio
et al
., 1984; Smith 1992; Riccio, Quagliariello,
1993; Beniac
et al
., 1997; Hu
et al
., 2004; Harauz
et al
., 2004). MBP can
also bind to other myelin proteins: myelin proteolipid protein [(PLP) (Golds,
Braun, 1978; Boggs, Wang, 2004)], and myelin 2
′
,3
′
-cyclic nucleotide
-phosphodiesterase [(CNP) (Dyer, Benjamins, 1989; Richter-Landsberg,
2001)]. MBP can bind to polyanionic proteins: calmodulin [(CaM) (Chan
et al
., 1994; Polverini
et al
., 2004)]; actin (Barylko, Dobrowolski, 1984;
Boggs
et al
., 2005); tubulin (Modesti, Barra, 1986; Gendreau
et al
., 2003)
and clathrin (Boggs, 2006). MBP can also bind to alfa
2
-macroglobulin
(Gunnarson
et al
., 1998, 2003) and heat shock protein 70 (Aquino
et al
.,
1998; Cwiklinska
et al
., 2003). Adherence of MBP to T cells has been
reported (Bobba
et al
., 1991).
According to their ability to interact with different ions, molecules
and cells, all MBP isoforms seem to fulfil different functions in
myelin (Boggs, 2006), and seem to be involved also in apparently
unrelated activities outside the CNS (Harauz
et al
., 2004). In fact,
besides the main role in compacting myelin, MBP may be involved
in various different functions, such as modulation of signal transduc-
tion pathways (Dyer, 1997; Campagnoni
et al
., 2003), and induction of
insulin and glucagon release from the pancreas (Kolehmainen,
Sormunen, 1998).
3
′
Search WWH ::
Custom Search