Biology subjects

Konopka, A.

Publications and source records attributed to Konopka, A..

3 recordsLinked to original sources

bioRxiv2023

Heterogeneity of radial spokes structural components and associated enzymes in Tetrahymena cilia

Radial spokes, RS1-RS2-RS3, are T-shaped, multiprotein complexes that transmit regulatory signals from central apparatus to outer doublet dyneins. RSs, especially RS3, differ in morphology, protein composition, and RS base-docked IDAs. Spokes defects alter cilia beating frequency, waveform, and amplitude leading, in humans, to primary ciliary dyskinesia and infertility. In contrast to RS1 and RS2, the protein composition of RS3 is partly resolved. Moreover, the role of particular spokes is unclear. Ciliate Tetrahymena thermophila has three Rsp3 paralogs and two or three paralogs of some other RSPs. Using multiple complementary approaches, we showed that Tetrahymena forms RS1 and RS2 subtypes having core composed of various Rsp3 paralogs and one type of Rsp3-less RS3. We elucidated proteomes of RS subtypes and identified novel RS-associated proteins, including enzymatic proteins involved in local regulation of the ADP/ATP levels and protein phosphorylation, whose presence further diversifies RSs properties and likely functions. In briefRadial spokes differ in their protein composition and architecture. Studies in a ciliate Tetrahymena revealed Rsp3 paralogs-dependent RS1 and RS2 subtypes, Rsp3-less RS3, and diversity of the RSP3 mutants phenotype. Known RS components and newly identified structural and enzymatic proteins were assigned to particular RSs.

cell biology↗

bioRxiv2022

Activation of trace amine-associated receptor 1 (TAAR1) reduces alcohol drinking behaviors in mice

Alcohol dependence is characterized by the abnormal release of dopamine in the brain reward-related areas. Trace amine-associated receptor 1 (TAAR1) is a G Protein-Coupled Receptor that negatively regulates dopamine neurotransmission and thus is a promising target in the treatment of drug addiction. However, the role of TAAR1 in the regulation of alcohol abuse remains understudied. Here, we assessed the effect of TAAR1 activation on alcohol-drinking behaviors of C57Bl/6J female mice housed in IntelliCages. The animals were administered with either vehicle or TAAR1 full selective agonist, RO5256390, and tested for alcohol consumption, alcohol preference, and motivation for alcohol seeking. We found that mice with the highest preference for alcohol (high drinkers) in the RO5256390 group consumed less alcohol and had lower alcohol preference in comparison to high drinkers in the vehicle group, during 20 h of free alcohol access (FAA). We also found decreased alcohol consumption and alcohol preference comparing all animals in the RO5256390 to all animals in the vehicle group, during 20 h of FAA performed after the abstinence. These effects of RO5256390 lasted for the first 24 hours after administration that roughly corresponded to the compound level in the brain, measured by mass spectrometry. Finally, we found that administration of RO5256390 may attenuate motivation for alcohol seeking. Taken together, our findings reveal that activation of TAAR1 may transiently reduce alcohol drinking; thus, TAAR1 is a promising target for the treatment of alcohol abuse and relapse.

animal behavior and cognition↗

bioRxiv2019

Speaking in the brain: The interaction between words and syntax in producing sentences

This neuroimaging study investigated the neural infrastructure of sentence-level language production. We compared brain activation patterns, as measured with BOLD-fMRI, during production of sentences which differed in verb argument structures (intransitives, transitives, ditransitives) and the lexical status of the verb (known verbs or pseudo-verbs). An example for the type of sentence to be produced started a mini-block of six sentences with the same structure. For each trial, participants were first given the (pseudo-)verb followed by three geometric shapes to serve as verb arguments in the sentences. Production of sentences with known verbs yielded greater activation compared to those with pseudo-verbs in the core language network of left inferior frontal gyrus, the left posterior middle temporal gyrus, and a more posterior middle temporal region extending into the angular gyrus (LpMTG/AG), analogous to effects observed in language comprehension. Increasing the number of verb arguments led to greater activation in an overlapping left pMTG/AG area, particularly for known verbs, as well as in the bilateral precuneus. Thus, producing sentences with more complex structures using existing verbs lead to increased activation in the language network, suggesting some reliance on memory retrieval of stored lexical-syntactic information during sentence production. This study thus provides evidence from sentence-level language production in line with functional models of the language network that have so far been mainly based on single word production, comprehension and processing in aphasia.

neuroscience↗