| Literature References | 1. YU, J.S. AND YANG, S.D.
Phosphorylation activation of phosphorylase-b kinase by cAMP,
Ca2+-independent, autophosphorylation-dependent protein-kinase.
BIOCHEM.BIOPHYS.RES.COMMUN. 207 140-147 (1995).
2. POLISHCHUK, S.V., BRANDT, N.R., MEYER, H.E., VARSANYI, M. AND
HEILMEYER, L.M.G.
Does phosphorylase-kinase control glycogen biosynthesis in skeletal muscle.
FEBS LETT. 362 271-275 (1995).
3.ZEMSKOVA, M.A., SHUR, S.A., SKOLYSHEVA, L.K. AND VULFSON, P.L.
Association of rabbit skeletal muscle phosphorylase kinase with sarcoplasmic
reticulum membranes.
BIOCHEMISTRY 60 1457-1463 (1995).
4. YU, J.S., LEE, S.C. AND YANG, S.D.
Effect of Mg2+ concentrations on phosphorylation activation of phosphorylase
b kinase by cAMP/Ca2+ independent, autophosphorylation-dependent protein
kinase.
J.PROTEIN CHEM. 14 747-752 (1995).
5. KURGANOV, B.I., ANDREEVA, I.E., MAKEEVA, V.F. AND LIVANOVA, N.B.
Hystereticproperties of rabbit skeletal muscle phosphorylase kinase:
Synergistic activation by phosphorylase b, Ca2+, and Mg2+.
BIOCHEM.MOL.BIOL.INT. 39 805-812 (1996).
6. LAFORET, P., EYMARD, B., LOMBES, A., DUBOC, D., JEHENSON, P.,
ROCCHICCIOLI, F., CHAUSSAIN, M., CHATEAU, D., BRUNET, P. AND FARDEAU, M.
Exercise intolerance due to muscular phosphorylase kinase deficiency.
Contribution of in vivo metabolism investigations.
REV.NEUROL. 152 458-464 (1996).
7. SAHIN, G., GUNGOR, T., RETTWITZVOLK, W., SCHOLTE, W., SHIN, Y.S.,
PODSKARBI, T. AND SEWELL, A.C.
Infantile muscle phosphorylase-b-kinase deficiency. A case report.
NEUROPEDIATRICS 29 48-50 (1998).
8. KAGALWALLA, A.F., KAGALWALLA, Y.A., ALAJAJI, S., GORKA, W. AND ASHRAF, M.
Phosphorylase-b kinase deficiency glycogenosis with cirrhosis of the liver.
J.PEDIATRICS 127 602-605 (1995).
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| Documentation | Phosphorylase b kinase (EC 2.7.1.38) belongs to a family of proteins
involved in glycogen biosynthesis [1]. The protein has a subunit composition
of (alpha, beta, gamma, delta)4, where the alpha and beta subunits are
regulatory, delta is calmodulin, and the gamma subunit is catalytic. The
enzyme is believed to have a dual role: the first is connected with glycogen
degradation via phosphorylation of glycogen phosphorylase; the second
controls glycogen biosynthesis on the sarcoplasmic reticular membrane more
directly by phosphorylation, and thus inhibition, of glycogen synthase [2].
The gamma catalytic chain contains three domains; one protein kinase and two
calmodulin-binding domains. Calcium and magnesium ions, together with cyclic
AMP, positively affect the efficiency of the enzyme, which is believed to
be associated with its auto-kinase activity [1,3-5].
The full extent of the effects of deficiencies in this enzyme in humans is
unknown; but case studies have been documented [6-8] that detail symptoms as
mild as `exercise intolerance' [6], to infant mortality arising from floppy
infant syndrome [7].
PHOSPHBKNASE is a 7-element fingerprint that provides a signature for the
phosphorylase kinase family. The fingerprint was derived from an initial
alignment of 7 sequences: the motifs were drawn from conserved regions
spanning the full alignment length - in the kinase domain, motif 1 spans
the C-terminus of helix 2 and the N-terminus of helix 3; motif 2 spans
helices 12 and 13; and the remaining motifs reside in the calmodulin-binding
domains. Two iterations on OWL30.2 were required to reach convergence, at
which point a true set comprising 8 sequences was identified.
An update on SPTR37_9f identified a true set of 7 sequences.
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