Disease relevance of Qk

• Parkin is mutated in autosomal recessive juvenile Parkinsonism and deletions in mice are associated with the mouse mutant Quaking (viable) [1].
• Mutant Quaking mice (C57BL/6J) display convulsive tonic-clonic seizures that can be either spontaneous or triggered by manipulation of the animal or by auditory stimulation [2].

High impact information on Qk

• The quaking (Qk) locus expresses a family of RNA binding proteins, and the expression of several alternatively spliced isoforms coincides with the development of oligodendrocytes and the onset of myelination [3].
• Fibroblasts (3T3) were plated onto culture substrata consisting of optic nerve tissue sections cut from normal or two myelin-deficient mutant mice, Shiverer and Quaking [4].
• In contrast, there was no difference in the level of Cu/Zn-SOD activity in the cerebrum of Qk, Shi, and Tr mice and their respective controls [5].
• Protein compositions were determined for sciatic nerve myelin isolated from young and adult control and quaking (Qk) mice [6].
• Thus, our data suggest that the Qk mutation has a similar effect on peripheral nervous system (PNS) and CNS basic proteins [6].

Biological context of Qk

• The effect of 5-hydroxytryptophan (5-HTP) on brain stem auditory evoked response (BAER) amplitude in Quaking (qk) and normal littermate mice was examined [7].
• Since Quaking and immature mice have many uncompacted myelin lamellae, these preliminary results suggest that phosphorylation and dephosphorylation could be involved in compaction mechanisms [8].

Anatomical context of Qk

• Myelin and premyelin material denser than myelin were obtained from quaking (Qk), shiverer (Shi), and myelin-deficient (mld) mutant and control mice, using zonal centrifugation on zonal rotor [9].
• Palmityl-CoA and stearyl-CoA desaturase in mouse brain microsomes during development in normal and neurological mutants (Quaking and Jimpy) [10].
• The diminution of the myelin ethanolamine plasmalogen in brain of the Jimpy mouse and brain and spinal cord of the Quaking mouse as visualized by thin-layer chromatography [11].
• The results suggest that an increase in noradrenergic neurotransmission in the brain stem, rather than in the cerebral cortex, could contribute to the behavioural abnormalities exhibited by the Quaking mice [12].
• Ultrastructural alterations in synaptic boutons of Quaking mice: dense clusters of small vesicles [13].

Associations of Qk with chemical compounds

• Cholesterol esters and the ester-metabolizing enzymes in Jimpy and Quaking mouse brains [14].
• The rate of disappearance of noradrenaline in the cerebral cortex and the brain stem after injection of FLA 63 was identical in control and Quaking mice [12].
• The 3H/14C ratio for the myelin subfraction was 1.88 as compared to a 3H/14C ratio of 3.0 for the other subfractions, indicating a 40% decrease in glycine incorporation into myelin of Quaking mice [15].
• The increased adenylate cyclase activity in the Quaking mice was in contrast to a lower cyclic AMP level and could not be accounted for by an alteration in phosphodiesterase activity [16].
• The calcium-dependent electrically evoked overflow of 3H-noradrenaline from slices of occipital cortex was inhibited by clonidine and enhanced by yohimbine in Quaking as well as in normal mice [12].

Regulatory relationships of Qk

• Adenylate cyclase activity was stimulated by norepinephrine in both control and Quaking animals [16].

Other interactions of Qk

• We have identified the mouse mutant Quaking as a spontaneously occurring PRKN knockout [17].
• Staining patterns with myelin associated glycoprotein and myelin basic protein also suggest that normal myelination occurs in grafts transplanted to the brains of Quaking mice [18].
• The Quaking mouse animals used as hosts are characterized by defective myelin associated glycoprotein [18].
• Brain-specific antigens in the Quaking mouse during ontogeny [19].
• Investigation of the changes in carbonic anhydrase activity as a function of age showed a cessation in enzyme accumulation in Quaking mice at around 20 days postnatally, suggesting an abnormality in cellular development [16].

Analytical, diagnostic and therapeutic context of Qk

• Fragments of normal embryonic cerebellum were transplanted into adult Quaking mice to examine using peroxidase-antiperoxidase immunocytochemistry the development of genetically normal tissue in an abnormal host environment [18].
• Immunohistochemical localization of Wolfgram proteins has been studied by the indirect immunoperoxidase technique with Wolfgram protein W1 antibodies in the nervous system of myelin deficient mutant mice: Jimpy, MSD and Quaking [20].
• In contrast to the occipital cortex, in the brain stem, the amount of neurotransmitter released by electrical stimulation was significantly increased in Quaking mice when compared with controls [12].

References