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Holley, A.

Publications and source records attributed to Holley, A..

3 recordsLinked to original sources

Molecular and cell type-specific determinants of inferior colliculus development and auditory function

Sound perception requires sensory information processing through brain regions where alterations to cellular composition or function may impact auditory-relevant behaviors. The inferior colliculus (IC) is a central midbrain hub for integrating and transforming auditory information prior to relay to the forebrain. However, the molecular logic that underlies the cell type specification of the IC remains unknown. Here, using a multiomic approach, we define the transcriptional and chromatin landscapes that underlie IC cell type diversity. We identify distinct glutamatergic neuronal subclasses and the gene regulatory programs that drive their specification, maturation, and survival. We show that perturbation to the transcription factor FOXP2, previously implicated in speech and language as well as brain disorders with altered sensory processing, selectively disrupts the specification and survival of three newly defined glutamatergic neuronal subclasses. We link these molecular and cellular disruptions to functional deficits in auditory processing including altered brainstem and forebrain responses and impaired behavioral sensitivity to acoustic stimuli. Together, these results link gene regulatory mechanisms to cell type-specification in the IC, providing insight into how molecular control of neuronal identity in midbrain sensory centers contributes to systems-level processing of sound.

neuroscience↗

An open source MALDI-TOF mass spectrometry database for the identification of North American tick species of medical and veterinary importance.

Matrix-assisted laser desorption/ionization coupled with time-of-flight mass spectrometry (MALDI-TOF MS) is a fast emerging and robust method for rapid and accurate characterization of arthropod vectors. Correct identification of ticks is key in monitoring medically or veterinary relevant species and associated pathogens. It has been extensively used for tick identification based on leg proteins; however, in North America, MALDI-TOF MS has not been explored for comprehensive identification of ticks, except for a few studies focusing on a limited number of species. Herein, we have generated proteomic spectral profiles of nine North American tick species belonging to five genera obtained from laboratory-maintained colonies. From the 407 high-quality MS spectra generated in this study, 44 were deposited in our newly made database and used as reference. All remaining MS spectra were used to query and validate the database. All specimens were identified correctly to the species level using MALDI-TOF MS, with reliable Log Score Values (LSVs) ranging from 1.72 to 2.86, and median and mean values of 2.41 and 2.40, respectively. A single exception noted: an Amblyomma mixtum was misidentified as Amblyomma tenellum. As a cost-effective, user-friendly, and high-throughput method, MALDI-TOF MS can serve as an alternative for accurately identifying tick species of veterinary and public health importance in North America, thereby supporting tick-borne disease surveillance efforts.

microbiology↗

Genetic admixture patterns in Argentinian Patagonia

As for other Latin American populations, Argentinians are the result of the admixture amongst different continental groups, mainly from America and Europe, and to a lesser extent from Sub-Saharan Africa. However, it is known that the admixture processes did not occur homogeneously throughout the country. Therefore, considering the importance for anthropological, medical and forensic researches, this study aimed to investigate the population genetic structure of the Argentinian Patagonia, through the analysis of 46 ancestry informative markers, in 433 individuals from five different localities. Overall, in the Patagonian sample, the average individual ancestry was estimated as 35.8% Native American (95% CI: 32.2-39.4%), 62.1% European (58.5-65.7%) and 2.1% African (1.7-2.4%). Comparing the five localities studied, statistically significant differences were observed for the Native American and European contributions, but not for the African ancestry. The admixture results combined with the genealogical information revealed intra-regional variations that are consistent with the different geographic origin of the participants and their ancestors. As expected, a high European ancestry was observed for donors with four grandparents born in Europe (96.8%) or in the Central region of Argentina (85%). In contrast, the Native American ancestry increased when the four grandparents were born in the North (71%) or in the South (61.9%) regions of the country, or even in Chile (60.5%). In summary, our results showed that differences on continental ancestry contribution have different origins in each region in Patagonia, and even in each locality, highlighting the importance of knowing the origin of the participants and their ancestors for the correct interpretation and contextualization of the genetic information.

genetics↗