Skip to main content

Table 2 Reactions and rate constants of signal transduction for DARPP-32 phosphorylation in dendrites of medium spiny neurons in the striatum (see legend of Figure 1 for abbreviations)

From: The internal state of medium spiny neurons varies in response to different input signals

Reaction Kf(nM-1. s-1)# Kb (s-1) Kc (s-1) Ref.
D1 + DA ↔ D1_DA 1.1E-3 10.0   [47]
D1_DA + Gαβγ ↔ D1_DA_Gαβγ 6.0E-4 1.0E-3   [47]
D1 + Gαβγ ↔ D1_Gαβγ 6.0E-5 3.0E-4   [47]
D1_Gαβγ+ DA ↔ D1_DA_Gαβγ 3.3E-3 10.0   [47]
D1_DA_Gαβγ → D1_DA + GαGTP+ Gβγ 20.0a    [47]
GαGTP → GαGDP 10.0a    [47]
GαGDP + Gβγ → Gαβγ 100.0    [47]
GαGTP + AC5 ↔ GαGTP_AC5 3.9E-2 50.0   [47]
GαGTP_AC5 + ATP ↔ GαGTP_AC5_ATP 1.3E-4 2.6E-1   [47]
GαGTP_AC5_ATP ↔ GαGTP_AC5 + cAMP 28.5a 2.6E-4b   [47]
PKA + 2 cAMP ↔ PKA_cAMP2 1.3E-5c 6.0E-3   [47]
PKA_cAMP2 + 2 cAMP ↔ PKA_cAMP4 1.7E-5c 6.0E-2   [47]
PKA_cAMP4 ↔ 2 PKAc + PKAr 5.1E-4a 4.8E-3c   [47]
PDE1 + cAMP ↔ PDE1_cAMP → PDE1 + AMP 2.0E-2 72.0 18.0 [47]
PDE4 + cAMP ↔ PDE4_cAMP → PDE4 + AMP 2.0E-2 72.0 18.0 [47]
PKAc + PDE1 ↔ PKAc_PDE1 → PKAc + PDE1p 6.0E-3 36.0 9.0 [48]
PDE1p → PDE1 1.0E-1a    [48]
PKAc + PDE4 ↔ PKAc_PDE4 → PKAc + PDE4p 6.0E-3 36.0 9.0 [48]
PDE4p → PDE4 1.0E-1a    [48]
→ Ca2+ 2.5E+1e    [48]
Ca2+ 0.6a/1.7a    [48]
2 Ca2+ + PP2Bi ↔ PP2Bi_Ca2 1.0E-3c 1.0   [48]
2 Ca2+ + PP2Bi_Ca2 ↔ PP2B 3.0E-3c 1.0   [48]
AC5 + Ca2+ ↔ AC5_Ca 1.0E-3 0.9   [47]
GαGTP + AC5_Ca ↔ GαGTP_AC5_Ca 1.9E-2 25.0   [47]
GαGTP_AC5_Ca + ATP ↔ GαGTP_AC5_Ca_ATP 6.0E-5 1.3E-1   [47]
GαGTP_AC5_Ca_ATP ↔ GαGTP_AC5_Ca + cAMP 14.2a 1.3E-4b   [47]
PP2A + 4 Ca2+ ↔ PP2Ac 7.7E-12d 1.0E-2   [47]
PP2A + PKAc ↔ PP2A_PKAc → PP2Ap + PKAc 2.5E-3 0.3 0.1 [49]
PP2Ap → PP2A 4.0E-3a    [47]
CK1 → CK1p 1.0a    [47]
PP2B + CK1p ↔ PP2B_CK1p → PP2B + CK1 3.0E-2 24.0 6.0 [47]
CDK5 + Ca2+ ↔ CDK5c 3.0E-3 1.0   
  1. a: Unit in s-1; b: Unit in nM-1·s-1; c: Unit in nM-2·s-1; d: Unit in nM-4·s-1; e: Unit in nM·s-1
  2. #: For a chemical reaction, Kf is the rate constant for the forward process, Kb is the rate constant for the backward process, while Kc is the rate constant for the catalytic step in a Michaelis-Menten kinetics.
\