@article{WaiderPoppMlinaretal.2019,
  author    = {Waider, Jonas and Popp, Sandy and Mlinar, Boris and Montalbano, Alberto and Bonfiglio, Francesco and Aboagye, Benjamin and Thuy, Elisabeth and Kern, Raphael and Thiel, Christopher and Araragi, Naozumi and Svirin, Evgeniy and Schmitt-B{\"o}hrer, Angelika G. and Corradetti, Renato and Lowry, Christopher A. and Lesch, Klaus-Peter},
  title     = {Serotonin deficiency increases context-dependent fear learning through modulation of hippocampal activity},
  series = {Frontiers in Neuroscience},
  volume    = {13},
  journal   = {Frontiers in Neuroscience},
  number    = {245},
  issn      = {1662-453X},
  doi       = {10.3389/fnins.2019.00245},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196077},
  year      = {2019},
  abstract  = {Brain serotonin (5-hydroxytryptamine, 5-HT) system dysfunction is implicated in exaggerated fear responses triggering various anxiety-, stress-, and trauma-related disorders. However, the underlying mechanisms are not well understood. Here, we investigated the impact of constitutively inactivated 5-HT synthesis on context-dependent fear learning and extinction using tryptophan hydroxylase 2 (Tph2) knockout mice. Fear conditioning and context-dependent fear memory extinction paradigms were combined with c-Fos imaging and electrophysiological recordings in the dorsal hippocampus (dHip). Tph2 mutant mice, completely devoid of 5-HT synthesis in brain, displayed accelerated fear memory formation and increased locomotor responses to foot shock. Furthermore, recall of context-dependent fear memory was increased. The behavioral responses were associated with increased c-Fos expression in the dHip and resistance to foot shock-induced impairment of hippocampal long-term potentiation (LTP). In conclusion, increased context-dependent fear memory resulting from brain 5-HT deficiency involves dysfunction of the hippocampal circuitry controlling contextual representation of fear-related behavioral responses.},
  language  = {en}
}
@article{LiuKinoshitaAdolfietal.2019,
  author    = {Liu, Ruiqi and Kinoshita, Masato and Adolfi, Mateus C. and Schartl, Manfred},
  title     = {Analysis of the role of the Mc4r system in development, growth, and puberty of medaka},
  series = {Frontiers in Endocrinology},
  volume    = {10},
  journal   = {Frontiers in Endocrinology},
  doi       = {10.3389/fendo.2019.00213},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201472},
  pages     = {213},
  year      = {2019},
  abstract  = {In mammals the melanocortin 4 receptor (Mc4r) signaling system has been mainly associated with the regulation of appetite and energy homeostasis. In fish of the genus Xiphophorus (platyfish and swordtails) puberty onset is genetically determined by a single locus, which encodes the mc4r. Wild populations of Xiphophorus are polymorphic for early and late-maturing individuals. Copy number variation of different mc4r alleles is responsible for the difference in puberty onset. To answer whether this is a special adaptation of the Mc4r signaling system in the lineage of Xiphophorus or a more widely conserved mechanism in teleosts, we studied the role of Mc4r in reproductive biology of medaka (Oryzias latipes), a close relative to Xiphophorus and a well-established model to study gonadal development. To understand the potential role of Mc4r in medaka, we characterized the major features of the Mc4r signaling system (mc4r, mrap2, pomc, agrp1). In medaka, all these genes are expressed before hatching. In adults, they are mainly expressed in the brain. The transcript of the receptor accessory protein mrap2 co-localizes with mc4r in the hypothalamus in adult brains indicating a conserved function of modulating Mc4r signaling. Comparing growth and puberty between wild-type and mc4r knockout medaka revealed that absence of Mc4r does not change puberty timing but significantly delays hatching. Embryonic development of knockout animals is retarded compared to wild-types. In conclusion, the Mc4r system in medaka is involved in regulation of growth rather than puberty.},
  language  = {en}
}
@article{BanickaMartensPanzeretal.2022,
  author    = {Banicka, Veronika and Martens, Marie Christine and Panzer, R{\"u}diger and Schrama, David and Emmert, Steffen and Boeckmann, Lars and Thiem, Alexander},
  title     = {Homozygous CRISPR/Cas9 knockout generated a novel functionally active exon 1 skipping XPA variant in melanoma cells},
  series = {International Journal of Molecular Sciences},
  volume    = {23},
  journal   = {International Journal of Molecular Sciences},
  number    = {19},
  issn      = {1422-0067},
  doi       = {10.3390/ijms231911649},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290427},
  year      = {2022},
  abstract  = {Defects in DNA repair pathways have been associated with an improved response to immune checkpoint inhibition (ICI). In particular, patients with the nucleotide excision repair (NER) defect disease Xeroderma pigmentosum (XP) responded impressively well to ICI treatment. Recently, in melanoma patients, pretherapeutic XP gene expression was predictive for anti-programmed cell death-1 (PD-1) ICI response. The underlying mechanisms of this finding are still to be revealed. Therefore, we used CRISPR/Cas9 to disrupt XPA in A375 melanoma cells. The resulting subclonal cell lines were investigated by Sanger sequencing. Based on their genetic sequence, candidates from XPA exon 1 and 2 were selected and further analyzed by immunoblotting, immunofluorescence, HCR and MTT assays. In XPA exon 1, we established a homozygous (c.19delG; p.A7Lfs*8) and a compound heterozygous (c.19delG/c.19_20insG; p.A7Lfs*8/p.A7Gfs*55) cell line. In XPA exon 2, we generated a compound heterozygous mutated cell line (c.206_208delTTG/c.208_209delGA; p.I69_D70delinsN/p.D70Hfs*31). The better performance of the homozygous than the heterozygous mutated exon 1 cells in DNA damage repair (HCR) and post-UV-C cell survival (MTT), was associated with the expression of a novel XPA protein variant. The results of our study serve as the fundamental basis for the investigation of the immunological consequences of XPA disruption in melanoma.},
  language  = {en}
}
@article{AraragiMlinarBaccinietal.2013,
  author    = {Araragi, Naozumi and Mlinar, Boris and Baccini, Gilda and Gutknecht, Lise and Lesch, Klaus-Peter and Corradetti, Renato},
  title     = {Conservation of 5-HT1A receptor-mediated autoinhibition of serotonin (5-HT) neurons in mice with altered 5-HT homeostasis},
  series = {Frontiers in Neuropharmacology},
  journal   = {Frontiers in Neuropharmacology},
  doi       = {10.3389/fphar.2013.00097},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97098},
  year      = {2013},
  abstract  = {Firing activity of serotonin (5-HT) neurons in the dorsal raphe nucleus (DRN) is controlled by inhibitory somatodendritic 5-HT1A autoreceptors. This autoinhibitory mechanism is implicated in the etiology of disorders of emotion regulation, such as anxiety disorders and depression, as well as in the mechanism of antidepressant action. Here, we investigated how persistent alterations in brain 5-HT availability affect autoinhibition in two genetically modified mouse models lacking critical mediators of serotonergic transmission: 5-HT transporter knockout (Sert-/-) and tryptophan hydroxylase-2 knockout (Tph2-/-) mice. The degree of autoinhibition was assessed by loose-seal cell-attached recording in DRN slices. First, application of the 5-HT1A-selective agonist R(+)-8-hydroxy-2-(di-n-propylamino)tetralin showed mild sensitization and marked desensitization of 5-HT1A receptors in Tph2-/- mice and Sert-/- mice, respectively. While 5-HT neurons from Tph2-/- mice did not display autoinhibition in response to L-tryptophan, autoinhibition of these neurons was unaltered in Sert-/- mice despite marked desensitization of their 5-HT1A autoreceptors. When the Tph2-dependent 5-HT synthesis step was bypassed by application of 5-hydroxy-L-tryptophan (5-HTP), neurons from both Tph2-/- and Sert-/- mice decreased their firing rates at significantly lower concentrations of 5-HTP compared to wildtype controls. Our findings demonstrate that, as opposed to the prevalent view, sensitivity of somatodendritic 5-HT1A receptors does not predict the magnitude of 5-HT neuron autoinhibition. Changes in 5-HT1A receptor sensitivity may rather be seen as an adaptive mechanism to keep autoinhibition functioning in response to extremely altered levels of extracellular 5-HT resulting from targeted inactivation of mediators of serotonergic signaling.},
  language  = {en}
}