Enter a Search String

Special character and space not allowed in the query term. Search string should be at least 2 characters long.

Search in:

ALL Accession Pathway Molecule Enzyme Reaction Connected to

Search for

Match

Anything Exact Word Starting With

By

Name Notes Model

Molecule Parameter List for craf-1*

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

craf-1* participated as	Molecule	Sum total of	Enzyme	Substrate of an enzyme	Product of an enzyme	Substrate in Reaction	Product in Reaction
No. of occurrences	1	0	0	2	2	1	0

Accession and Pathway Details

Accession Name	Accession No.	Accession Type	Pathway Link
EGFR_MAPK	58	Network	Shared_Object_EGFR_MAPK,  MAPK,  Ras,   EGFR,  Sos
Model of MAPK activation by EGFR in the synapse. Demonstration programs using this model are available here. Primary citation:Bhalla US. Biophys J. (2004) 87(2):745-53.

craf-1* acting as a Molecule in  EGFR_MAPK Network

Name	Accession Name	Pathway Name	Initial Conc. (uM)	Volume (fL)	Buffered
craf-1*	EGFR_MAPK Accession No. : 58	MAPK Pathway No. : 230	0	1000	No

craf-1* acting as a Substrate for an Enzyme in  EGFR_MAPK Network

	Enzyme Molecule / Enzyme Activity	Accession Name	Pathway Name	Km (uM)	kcat (s^-1)	Ratio	Enzyme Type	Reagents
1	MAPK*  / MAPK*-feedback	EGFR_MAPK Accession No. : 58	Shared_Object_ EGFR_MAPK Pathway No. : 229	25.641	10	4	explicit E-S complex	Substrate craf-1* Product craf-1**
	Ueki et al JBC 269(22):15756-15761 show the presence of this step, but not the rate consts, which are derived from Sanghera et al JBC 265(1):52-57, 1990, see the deriv in the MAPK* notes.
2	PPhosphatase2A  / craf-deph	EGFR_MAPK Accession No. : 58	Shared_Object_ EGFR_MAPK Pathway No. : 229	15.6566	6	4.16667	explicit E-S complex	Substrate craf-1* Product craf-1
	See parent PPhosphatase2A for parms

craf-1* acting as a Product of an Enzyme in  EGFR_MAPK Network

	Enzyme Molecule / Enzyme Activity	Accession Name	Pathway Name	Km (uM)	kcat (s^-1)	Ratio	Enzyme Type	Reagents
1	PKC-active  / PKC-act-raf	EGFR_MAPK Accession No. : 58	Shared_Object_ EGFR_MAPK Pathway No. : 229	66.6667	4	4	explicit E-S complex	Substrate craf-1 Product craf-1*
	Rate consts from Chen et al Biochem 32, 1032 (1993) k3 = k2 = 4 k1 = 9e-5 recalculated gives 1.666e-5, which is not very different. Looks like k3 is rate-limiting in this case: there is a huge amount of craf locked up in the enz complex. Let us assume a 10x higher Km, ie, lower affinity. k1 drops by 10x. Also changed k2 to 4x k3. Lowerd k1 to 1e-6 to balance 10X DAG sensitivity of PKC
2	PPhosphatase2A  / craf**-deph	EGFR_MAPK Accession No. : 58	Shared_Object_ EGFR_MAPK Pathway No. : 229	15.6566	6	4.16667	explicit E-S complex	Substrate craf-1** Product craf-1*
	Ueki et al JBC 269(22) pp 15756-15761 1994 show hyperphosphorylation of craf, so this is there to dephosphorylate it. Identity of phosphatase is not known to me, but it may be PP2A like the rest, so I have made it so.

craf-1* acting as a Substrate in a reaction in  EGFR_MAPK 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
Ras-act-craf	EGFR_MAPK Accession No. : 58	Shared_Object_ EGFR_MAPK Pathway No. : 229	24 (uM^-1 s^-1)	0.5 (s^-1)	Kd(bf) = 0.0208(uM)	-	Substrate GTP-Ras craf-1* Product Raf-GTP-Ras*
Assume the binding is fast and limited only by the amount of Ras* available. So kf=kb/[craf-1] If kb is 1/sec, then kf = 1/0.2 uM = 1/(0.2 * 6e5) = 8.3e-6 Later: Raise it by 10 X to 4e-5 From Hallberg et al JBC 269:6 3913-3916 1994, 3% of cellular Raf is complexed with Ras. So we raise kb 4x to 4 This step needed to memb-anchor and activate Raf: Leevers et al Nature 369 411-414 (I don't....