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Molecule Parameter List for CaMKII | The statistics table lists the distribution of a molecule acting either as a substrate, product, enzyme or as a molecule within the network.
The text color of a molecule is highlighted by  color. | | Statistics |
Accession and Pathway Details | |
| Accession Name | Accession No. | Accession Type | Pathway Link | NonOsc_Ca_
IP3metabolism | 31 | Network |
MIPP, CaMKII, CaM,
PKC, IP3-3K, CaRegulation,
Gq, PLCbeta, 134_dephos,
145_dephos, IP4-system, IHP-system,
1345_dephos | | This network models detailed metabolism of Ins(145)P3, integrated with GPCR mediated PLCbeta activation and Ca release by the InsP3 receptor in the neuron. It is similar to the NonOsc_Ca_IP3metab model (accession 23) except that some enzymes have been modified to have reversible kinetics rather than Michaelis-Menten kinetics. These modified enzymes belong to the groups: IP4-system, IP3-3K, 145_dephos and 134_dephos. Mishra J, Bhalla US. Biophys J. 2002 Sep;83(3):1298-316. |
CaMKII acting as a Molecule in NonOsc_Ca_IP3metabolism Network
| Name | Accession Name | Pathway Name | Initial Conc.
(uM) | Volume
(fL) | Buffered | | CaMKII | NonOsc_Ca_
IP3metabolism
Accession No. : 31 | CaMKII
Pathway No. : 145 | 70 | 1000 | No | | Huge concentration of CaMKII. In PSD it is 20-40% of protein, so we assume it is around 2.5% of protein in spine as a whole. This level is so high it is unlikely to matter much if we are off a bit. This comes to about 70 uM. Seen the review: Hanson and Schulman 1992 Ann. Rev. Biuochem 60:559-601 |
CaMKII acting as a Product of an Enzyme in NonOsc_Ca_IP3metabolism Network
| | Enzyme Molecule /
Enzyme Activity | Accession Name | Pathway Name | Km (uM) | kcat (s^-1) | Ratio | Enzyme Type | Reagents | | 1 | PP1-active /
Deph-thr306 | NonOsc_Ca_
IP3metabolism
Accession No. : 31 | CaMKII
Pathway No. : 145 | 5.09907 | 0.35 | 4 | explicit E-S complex | Substrate
CaMK-thr306
Product
CaMKII
| | | Dephosphorylation tempkin are assumed to be the same for all phosphorylation sites on CaMKII. The rates are from Stralfors et al Eur J Biochem 149 295-303 giving Vmax = 5.7 umol/min giving k3 = 3.5/sec and k2 = 14. Foulkes et al Eur J Biochem 132 309-313 1983 give Km = 5.1 uM so k1 becomes 5.72e-6 Simonelli 1984 (Grad Thesis, CUNY) showed that other substrates are about 1/10 rate of phosphorylase a, so we reduce k1,k2,k3 by 10 to 5.72e-7, 1.4, 0.35. This gives the final Km of 5.1, and Vmax of 0.35/sec. | | 2 | PP1-active /
Deph_thr286b | NonOsc_Ca_
IP3metabolism
Accession No. : 31 | CaMKII
Pathway No. : 145 | 5.09907 | 0.35 | 4 | explicit E-S complex | Substrate
CaMKII-thr286
Product
CaMKII
| | | Rates are assumed to be the same for all phosphorylation sites on CaMKII. The rates are from Stralfors et al Eur J Biochem 149 295-303 giving Vmax = 5.7 umol/min giving k3 = 3.5/sec and k2 = 14. Foulkes et al Eur J Biochem 132 309-313 1983 give Km = 5.1 uM so k1 becomes 5.72e-6 Simonelli 1984 (Grad Thesis, CUNY) showed that other substrates are about 1/10 rate of phosphorylase a, so we reduce k1,k2,k3 by 10 to 5.72e-7, 1.4, 0.35. This gives the final Km of 5.1, and Vmax of 0.35/sec. |
CaMKII acting as a Substrate in a reaction in NonOsc_Ca_IP3metabolism Network
| Kd is calculated only for second order reactions, like nA+nB <->nC or nA<->nC+nD, where n is number and A,B,C,D are molecules, where as for first order reactions Keq is calculated.
Kd for higher order reaction are not consider. |
| | Name | Accession Name | Pathway Name | Kf | Kb | Kd | tau | Reagents | | 1 | CaMKII-bind-CaM | NonOsc_Ca_
IP3metabolism
Accession No. : 31 | CaMKII
Pathway No. : 145 | 49.9998
(uM^-1 s^-1) | 5
(s^-1) | Kd(bf) = 0.1(uM) | - | Substrate
CaM-Ca4
CaMKII
Product
CaMKII-CaM
| | | This is tricky. There is some cooperativity here arising from interactions between the subunits of the CAMKII holoenzyme. However, the stoichiometry is 1. Kd = 0.1 uM. Rate is fast (see Hanson et al Neuron 12 943-956 1994) Hanson and Schulman 1992 AnnRev Biochem 61:559-601 give tau for dissoc as 0.2 sec at low Ca, 0.4 at high. Low Ca = 100 nM = physiol. | | 2 | basal-activity | NonOsc_Ca_
IP3metabolism
Accession No. : 31 | CaMKII
Pathway No. : 145 | 0.003
(s^-1) | 0
(s^-1) | - | - | Substrate
CaMKII
Product
CaMKII-thr286
| | | This reaction represents one of the unknowns in CaMK-II biochemistry: what maintains the basal level of phosphorylation on thr 286 ? See Hanson and Schulman Ann Rev Biochem 1992 61:559-601, specially pg 580, for review. I have not been able to find any compelling mechanism in the literature, but fortunately the level of basal activity is well documented. Lisman et al propose that the levels of PP1 are very low in the postsynaptic density, and PP2A is excluded from the PSD, and this would lead to autophosphorylation at a sustained level. |
| Database compilation and code copyright (C) 2022, Upinder S. Bhalla and NCBS/TIFR
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