Biochemical and Biophysical Research Communications
Cdk5 phosphorylates CaV1.3 channels and regulates GABAA-mediated miniature inhibitory post-synaptic currents in striato-nigral terminals
Graphical abstract
Introduction
Transient elevations in the cytosolic Ca2+ concentration trigger membrane fusion, a key event in the vesicular release of neurotransmitters [1]. These changes in intracellular Ca2+ are mediated largely by the activity of voltage-gated Ca2+ (CaV) channels in the plasma membrane. Different types of CaV channels are expressed in the central nervous system, each with specific functional and pharmacological properties [2]. CaV channels are protein complexes composed of a main α1, and auxiliary α2δ, β, and γ subunits. Ten different CaVα1 subunits have been identified as corresponding to the native isoforms of the channels, divided into three subfamilies of proteins named CaV1, CaV2, and CaV3. The CaV1 subfamily (CaV1.1-CaV1.4) encodes the four different isoforms of the so-called L-type channels, and the CaV2 family (CaV2.1-CaV2.3) comprises the P/Q-, N-, and R-types, respectively [2]. The CaV3 subfamily (CaV3.1-CaV3.3) groups the low threshold T-type channels [3].
Diverse studies have shown the role of L-type channels in different neurotransmission systems. For example, micro-injection of an activator of these channels (BAYK8644) in the rat caudate-putamen nucleus increases extracellular dopamine, which is prevented by the application of the dihydropyridine antagonists of L-type channels (nimodipine or nicardipine). BAYK8644 also increases the release of [3H]-noradrenaline in brain cortex synaptosomes, an effect prevented by nimodipine and nitrendipine. Also, L-channels have been involved in GABA release in the rat substantia nigra pars reticulata (SNpr) and in the globus pallidus [4]. These data demonstrate that the L-type channels may play an important role in neurotransmitter release and contribute to the control of the SNpr by regulating GABA release.
L-type channels may also be regulated by the activity of protein kinases. About 250 protein kinases are expressed in the mammalian adult brain, and some of these are located at the pre-synaptic terminals (i.e., CaMKII, ERK 1/2, PI3K, PKA, and PKG), where they regulate a myriad of processes including learning and memory [5]. Nevertheless, the synaptic functions of many kinases remain undefined, such as in the case of cyclin-dependent kinase 5 (Cdk5), which play a role in multiple neuronal processes [6]. Interestingly, Cdk5 has been implicated in the regulation of neurotransmission, acting directly on CaV channels. In heterologous systems, over-expression of Cdk5 affect the activity, trafficking, and localization of CaV3 channels [7,8], increases the open probability of the CaV2.2 channels and facilitates the release of glutamate from hippocampal neurons [9]. Here, we present evidence that the L-type channels of the CaV1.3 class are expressed in striatal fibers projecting into the SNpr and are subjected to phosphorylation by Cdk5.
Section snippets
Animal and slice preparation
Neonatal or adult male Wistar rats were used for electrophysiology and for Western blot assays, respectively. All procedures were carried out in accordance with the NIH Guide for Care and Use of Laboratory Animals and were approved by the Animal Care Committee of Cinvestav-IPN (CICUAL). For electrophysiology, parasagittal brain slices (300-μm thick), containing the SNpr were incubated in artificial cerebrospinal fluid and transferred to a recording chamber. GABA-receptor-mediated currents were
Results and discussion
Recent evidence suggests that CaV1.2-class channels may be targets of Cdk5 phosphorylation [15]. However, it remains unknown whether the kinase may phosphorylate channels of the CaV1.3-class. Therefore, we sought to determine whether Cdk5 affects the activity of the CaV1.3 full-length channels heterologously expressed in HEK293 cells, using the inhibitor Olomoucine (Olo; 100 μM). The addition of Olo to the internal recording solution significantly increased the density of the currents through Ca
Author contributions
SL-L, AS, RG-R, RF, and BF conceived and designed the experiments, contributed reagents and conducted data analysis. RF wrote the manuscript. SL-L, AS, RG-R, AC-R, AA-F, MR-S, RC, and DT-S conducted the experiments.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
This work was supported by Conacyt (grant 2674) to RF, and from PAPIIT-UNAM (grant IN211018) to AS.
References (20)
- et al.
T-type calcium channels: from molecule to therapeutic opportunities
Int. J. Biochem. Cell Biol.
(2019) - et al.
L-type Ca2⁺ channel activity determines modulation of GABA release by dopamine in the substantia nigra reticulata and the globus pallidus of the rat
Neuroscience
(2014) - et al.
Regulation of N-type voltage-gated calcium channels and presynaptic function by cyclin-dependent kinase 5
Neuron
(2012) - et al.
C-terminal modulatory domain controls coupling of voltage-sensing to pore opening in CaV1.3 L-type Ca2+ channels
Biophys. J.
(2014) - et al.
Cloning and expression of a neuronal calcium channel beta subunit
J. Biol. Chem.
(1993) - et al.
CaV1.2 channels mediate persistent chronic stress-induced behavioral deficits that are associated with prefrontal cortex activation of the p25/Cdk5-glucocorticoid receptor pathway
Neurobiol. Stress
(2017) - et al.
Functional properties of a newly identified C-terminal splice variant of CaV1.3 L-type Ca2+ channels
J. Biol. Chem.
(2011) - et al.
CDKs: taking on a role as mediators of dopaminergic loss in Parkinson’s disease
Trends Mol. Med.
(2004) - et al.
Distinctive properties of a neuronal calcium channel and its contribution to excitatory synaptic transmission in the central nervous system
Adv. Second Messenger Phosphoprotein Res.
(1994) - et al.
The physiology, pathology, and pharmacology of voltage-gated calcium channels and their future therapeutic potential
Pharmacol. Rev.
(2015)
Cited by (6)
Targeting protein kinases for the treatment of Alzheimer's disease: Recent progress and future perspectives
2023, European Journal of Medicinal ChemistryL5-6 Spinal Nerve Ligation-induced Neuropathy Changes the Location and Function of Ca<sup>2+</sup> Channels and Cdk5 and Affects the Compound Action Potential in Adjacent Intact L4 Afferent Fibers
2021, NeuroscienceCitation Excerpt :The quantitative analysis of the cAPs showed no significant changes in the latency of the rapid fibers' response. As mentioned earlier, previous work from our research group has shown that Cdk5 exerts stimulatory effects on CaV3 channels (Calderón-Rivera et al., 2015; Gomez et al., 2020a; Loya-López et al., 2020). Consequently, we investigated whether the modification in the cAP caused by olomoucine was related to a possible reduction in these channels' functional expression.
Valproic Acid-Induced Anxiety and Depression Behaviors are Ameliorated in p39 Cdk5 Activator-Deficient Mice
2022, Neurochemical ResearchInhibition of cdk5 in pv neurons reactivates experience‐dependent plasticity in adult visual cortex
2022, International Journal of Molecular Sciences