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Drosophila melanogaster exhibits multiple highly sophisticated temperaturesensing systems, enabling its effective response and navigation to temperature changes. Previous research has identified three dorsal organ cool cells (DOCCs) in fly larvae, consisting of two A-type and one B-type cell with distinct calcium dynamics. When subjected to hypertonic conditions, calcium imaging shows that A-type DOCCs maintain their responses to cool temperatures. In contrast, a subset of B-type DOCCs does not exhibit detectable GCaMP baseline signals, and the remaining detectable B-type DOCCs exhibit reduced temperature responses. The activation of both A-type and B-type DOCCs depends on the same members of the ionotropic receptor (IR) family: IR21a, IR93a, and IR25a. A-type DOCCs exhibit a higher somal level of IR93a than B-type DOCCs. Overexpression of Ir93a restores B-type calcium responses to cool temperatures, but not the proportion of B-type cells with a detectable GCaMP baseline, in a hypertonic environment, suggesting a selective role of IR93a in maintaining the temperature responses under hypertonic conditions. Our findings identify a novel function of B-type DOCCs in integrating temperature and tonic stimuli. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the molecular mechanism of the Jk(a‐b‐) phenotype in a Chinese transfusion patient. Background: Many different mutation types relating to Jk(a‐b‐) phenotype have been reported. However, the splice‐site mutation is relatively rare and the related functional verification is lacking. Materials and Methods: In this study, the blood sample was collected from a transfusion patient with the Jk(a‐b‐) phenotype. Serotyping was performed using routine serological methods. The exons sequences and coding regions of the JK gene were amplified using polymerase chain reaction and directly sequenced. To perform a minigene splicing assay, the intronic mutation sequences were cloned into a pSPL3 splice reporting vector. The splicing reporter minigene assay was performed in HEK 293T cells. Results: The Jk(a‐b‐) phenotype of the blood sample was identified through serological testing. Sequencing results revealed that the sample had a novel homozygous splice‐site mutation JK*02N (NM_015865.7: c.663+3A>C). Further analysis, including cDNA sequencing and minigene splicing assay, confirmed that the novel splice‐site mutation resulted in exon skipping. Interestingly, different numbers of exons being skipped were obtained by the two methods. Conclusion: This study revealed a novel homozygous splicing‐site mutation associated with the Jk(a‐b‐) phenotype in Chinese population. Our results emphasise the importance of the in vitro functional method minigene splicing assay, while also acknowledging its potential limitations when compared to cDNA sequencing. [ABSTRACT FROM AUTHOR]

Aim: To investigate the clinical application of thromboelastography (TEG) in severe fever with thrombocytopenia syndrome (SFTS). Methods: One hundred and fifty-seven patients with SFTS were included in the study. The participants were distributed into 3 groups; A, B, and C. And 103 patients in group A met the clinical criteria as they exhibited slight liver and kidney dysfunction. Group B consisted of 54 patients with SFTS who were critically ill while group C was a healthy control group with 58 participants. Results: Patients with SFTS exhibited lower coagulation than the healthy participants. Group B patients exhibited significantly lower coagulation compared to group A. There was no significant difference in platelet count and fibrinogen content between patients in group A and group B, but platelet aggregation function and fibrinogen activity were significantly lower in group B patients. Conclusion: Our results suggest that it is risky to solely rely on platelet count and the fibrinogen in SFTS. Monitoring of TEG and other coagulation indexes should be emphasized. [ABSTRACT FROM AUTHOR]

After previously discovering that the ion channel TRPA1 is used as an internal temperature sensor in Drosophila to control the slow response of flies to shallow thermal gradients, the authors show here that the rapid response of flies to steep warming gradients relies on a different protein, GR28B, providing the first example of a thermosensory role for a gustatory receptor. A novel thermosensor in Drosophila Flies use the TRPA1 ion channel as an internal temperature sensor to slowly adjust their response to shallow thermal gradients. Now Paul Garrity and colleagues show that the rapid response of flies exposed to steep warmth gradients does not require TRPA1, but instead relies on the gustatory receptor GR28B(D), acting in peripheral thermosensing cells. Gustatory receptors have been implicated in taste, olfaction and host-seeking by disease-vector insects, but have not previously been linked with thermosensation. Behavioural responses to temperature are critical for survival, and animals from insects to humans show strong preferences for specific temperatures.sup.1,2. Preferred temperature selection promotes avoidance of adverse thermal environments in the short term and maintenance of optimal body temperatures over the long term.sup.1,2, but its molecular and cellular basis is largely unknown. Recent studies have generated conflicting views of thermal preference in Drosophila, attributing importance to either internal.sup.3 or peripheral.sup.4 warmth sensors. Here we reconcile these views by showing that thermal preference is not a singular response, but involves multiple systems relevant in different contexts. We found previously that the transient receptor potential channel TRPA1 acts internally to control the slowly developing preference response of flies exposed to a shallow thermal gradient.sup.3. We now find that the rapid response of flies exposed to a steep warmth gradient does not require TRPA1; rather, the gustatory receptor GR28B(D) drives this behaviour through peripheral thermosensors. Gustatory receptors are a large gene family, widely studied in insect gustation and olfaction, and are implicated in host-seeking by insect disease vectors.sup.5,6,7, but have not previously been implicated in thermosensation. At the molecular level, GR28B(D) misexpression confers thermosensitivity upon diverse cell types, suggesting that it is a warmth sensor. These data reveal a new type of thermosensory molecule and uncover a functional distinction between peripheral and internal warmth sensors in this tiny ectotherm reminiscent of thermoregulatory systems in larger, endothermic animals.sup.2. The use of multiple, distinct molecules to respond to a given temperature, as observed here, may facilitate independent tuning of an animal's distinct thermosensory responses., Author(s): Lina Ni [sup.1] [sup.2] , Peter Bronk [sup.1] [sup.2] , Elaine C. Chang [sup.1] [sup.2] , April M. Lowell [sup.1] [sup.2] , Juliette O. Flam [sup.1] [sup.2] , Vincent [...]

Highly temperature-responsive TRP cation channels, thermoTRPs, mediate thermosensation from insects to mammals (1,2) and are important for human pain and inflammation (6). Like mammalian thermoTRPs, Drosophila melanogaster TRPA1 is both [...], Discriminating among sensory stimuli is critical for animal survival. This discrimination is particularly essential when evaluating whether a stimulus is noxious or innocuous. From insects to humans, transient receptor potential (TRP) channels are key transducers of thermal, chemical and other sensory cues (1,2). Many TRPs are multimodal receptors that respond to diverse stimuli (1-3), but how animals distinguish sensory inputs activating the same TRP is largely unknown. Here we determine how stimuli activating Drosophila TRPA1 are discriminated. Although Drosophila TRPA1 responds to both noxious chemicals (4) and innocuous warming (5), we find that TRPA1-expressing chemosensory neurons respond to chemicals but not warmth, a specificity conferred by a chemosensory-specific TRPA1 isoform with reduced thermosensitivity compared to the previously described isoform. At the molecular level, this reduction results from a unique region that robustly reduces the channel's thermosensitivity. Cell-type segregation of TRPA1 activity is critical: when the thermosensory isoform is expressed in chemosensors, flies respond to innocuous warming with regurgitation, a nocifensive response. TRPA1 isoform diversity is conserved in malaria mosquitoes, indicating that similar mechanisms may allow discrimination of host-derived warmth--an attractant--from chemical repellents. These findings indicate that reducing thermosensitivity can be critical for TRP channel functional diversification, facilitating their use in contexts in which thermal sensitivity can be maladaptive.