Brain-derived neurotrophic factor modulation of Kv1.3 channel is disregulated by adaptor proteins Grb10 and nShc

BMC Neuroscience

Table 1 The effect of adaptor proteins on TrkB kinase-induced Kv1.3 current properties.

Transfection Condition	Modulator	Peak current (pA)	τ_Inact (msec)	τ_Deact (msec)	V_1/2 (mV)	κ
Kv1.3	BDNF
Pre		287 ± 49 (4)	794 ± 252	31.5 ± 5.4	-38.2 ± 5.8	4.2 ± 0.7
Post		303 ± 68	961 ± 263	38.3 ± 13.2	-41.5 ± 6.8	4.9 ± 1.1
Kv1.3 + Grb10	BDNF
Pre		506 ± 271 (4)	774 ± 110	31.3 ± 4.5	-39.4 ± 6.1	5.4 ± 0.4
Post		498 ± 246	*610 ± 127	34.2 ± 4.7	-41.5 ± 6.8	4.4 ± 2.6
Kv1.3 + nShc	BDNF
Pre		543 ± 176 (7)	770 ± 45	32.6 ± 4.3	-45.0 ± 2.5	4.3 ± 0.6
Post		586 ± 107	817 ± 54	31.4 ± 4.0	-41.4 ± 3.3	3.9 ± 0.9
Kv1.3 + TrkB	Vehicle
Pre		551 ± 198 (4)	788 ± 186	37.2 ± 3.3	-40.4 ± 5.0	5.1 ± 0.5
Post		557 ± 183	742 ± 130	32.3 ± 3.3	-38.6 ± 5.8	5.4 ± 0.7
Kv1.3 + TrkB	BDNF
Pre		555 ± 173 (7)	900 ± 243	36.8 ± 2.9	-36.2 ± 4.6	5.8 ± 1.1
Post		*442 ± 173	762 ± 151	38.8 ± 6.7	-40.3 ± 6.7	5.3 ± 1.4
Kv1.3 + TrkB + Grb10	BDNF
Pre		488 ± 114 (7)	862 ± 110	29.3 ± 3.5	-42.6 ± 3.7	6.7 ± 0.6
Post		545 ± 133	*553 ± 46	35.4 ± 5.5	*-54.1 ± 2.8	6.3 ± 1.4
Kv1.3 + TrkB + nShc	BDNF
Pre		343 ± 71 (13)	618 ± 67	37.4 ± 3.2	-40.9 ± 1.9	4.4 ± 0.7
Post		381 ± 92	549 ± 68	36.4 ± 2.0	-43.5 ± 2.9	4.4 ± 1.1

HEK 293 cells were transfected with cDNAs encoding Kv1.3 ± TrkB ki nase ± adaptor protein. Several voltage-stimulating paradigms were completed (see "Methods") to collect the tabled biophysical properties by cell-attached patch-clamp recording. Mean values (± s.e.m.) for peak current amplitude (pA), inactivation time constant (τ_Inact), deactivation time constant (τ_Deact), voltage at half activation (V_1/2), and slope (κ) of the voltage dependence were compared across various transfection conditions at the start of the patch recording (Pre) versus twenty minutes following 1 ng/μg BDNF (Post) using a paired t-test, α ≤ 0.05. * = Significantly different.

ISSN: 1471-2202