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1. The conserved molting/circadian rhythm regulator NHR-23/NR1F1 serves as an essential co-regulator of C. elegans spermatogenesis

   https://doi.org/10.1242/dev.193862  

   Ragle, James Matthew ; Aita, Abigail L. ; Morrison, Kayleigh N. ; Martinez-Mendez, Raquel ; Saeger, Hannah N. ; Ashley, Guinevere A. ; Johnson, Londen C. ; Schubert, Katherine A. ; Shakes, Diane C. ; Ward, Jordan D. ( November 2020 , Development)

   null (Ed.)

   In sexually reproducing metazoans, spermatogenesis is the process by which uncommitted germ cells give rise to haploid sperm. Work in model systems has revealed mechanisms controlling commitment to the sperm fate, but how this fate is subsequently executed remains less clear. While studying the well-established role of the conserved nuclear hormone receptor transcription factor, NHR-23/NR1F1, in regulating C. elegans molting, we discovered NHR-23/NR1F1 is also constitutively expressed in developing 1° spermatocytes and is a critical regulator of spermatogenesis. In this novel role, NHR-23/NR1F1 functions downstream of the canonical sex determination pathway. Degron-mediated depletion of NHR-23/NR1F1 within hermaphrodite or male germlines causes sterility due to an absence of functional sperm as depleted animals produce arrested primary spermatocytes rather than haploid sperm. These spermatocytes arrest in prometaphase I and fail to either progress to anaphase or attempt spermatid-residual body partitioning. They make sperm-specific membranous organelles (MOs) but fail to assemble their major sperm protein into fibrous bodies. NHR-23/NR1F1 appears to function independently of the known SPE-44 gene regulatory network, revealing the existence of an NHR-23/NR1F1-mediated module that regulates the spermatogenesis program. 

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2. De novo transcriptome assemblies of red king crab (Paralithodes camtschaticus) and snow crab (Chionoecetes opilio) molting gland and eyestalk ganglia - Temperature effects on expression of molting and growth regulatory genes in adult red king crab

   https://doi.org/10.1016/j.cbpb.2021.110678  

   Andersen, Øivind ; Johnsen, Hanne ; Wittmann, Astrid C. ; Harms, Lars ; Thesslund, Tina ; Berg, Ragnhild Stenberg ; Siikavuopio, Sten ; Mykles, Donald L. ( January 2022 , Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology)
3. Chronic, Intermittent Microdoses of the Psychedelic N , N -Dimethyltryptamine (DMT) Produce Positive Effects on Mood and Anxiety in Rodents

   https://doi.org/10.1021/acschemneuro.8b00692  

   Cameron, Lindsay P. ; Benson, Charlie J. ; DeFelice, Brian C. ; Fiehn, Oliver ; Olson, David E. ( March 2019 , ACS Chemical Neuroscience)
4. Chronic exposure to complex metal oxide nanoparticles elicits rapid resistance in Shewanella oneidensis MR-1

   https://doi.org/10.1039/C9SC01942A  

   Mitchell, Stephanie L. ; Hudson-Smith, Natalie V. ; Cahill, Meghan S. ; Reynolds, Benjamin N. ; Frand, Seth D. ; Green, Curtis M. ; Wang, Chenyu ; Hang, Mimi N. ; Hernandez, Rodrigo Tapia ; Hamers, Robert J. ; et al ( January 2019 , Chemical Science)

   Engineered nanoparticles are incorporated into numerous emerging technologies because of their unique physical and chemical properties. Many of these properties facilitate novel interactions, including both intentional and accidental effects on biological systems. Silver-containing particles are widely used as antimicrobial agents and recent evidence indicates that bacteria rapidly become resistant to these nanoparticles. Much less studied is the chronic exposure of bacteria to particles that were not designed to interact with microorganisms. For example, previous work has demonstrated that the lithium intercalated battery cathode nanosheet, nickel manganese cobalt oxide (NMC), is cytotoxic and causes a significant delay in growth of Shewanella oneidensis MR-1 upon acute exposure. Here, we report that S. oneidensis MR-1 rapidly adapts to chronic NMC exposure and is subsequently able to survive in much higher concentrations of these particles, providing the first evidence of permanent bacterial resistance following exposure to nanoparticles that were not intended as antibacterial agents. We also found that when NMC-adapted bacteria were subjected to only the metal ions released from this material, their specific growth rates were higher than when exposed to the nanoparticle. As such, we provide here the first demonstration of bacterial resistance to complex metal oxide nanoparticles with an adaptation mechanism that cannot be fully explained by multi-metal adaptation. Importantly, this adaptation persists even after the organism has been grown in pristine media for multiple generations, indicating that S. oneidensis MR-1 has developed permanent resistance to NMC. 

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5. Varying intensities of chronic stress induce inconsistent responses in weight and plasma metabolites in house sparrows ( Passer domesticus )

   https://doi.org/10.7717/peerj.15661  

   Beattie, Ursula K. ; Fefferman, Nina ; Romero, L. Michael ( January 2023 , PeerJ)

   One of the biggest unanswered questions in the field of stress physiology is whether variation in chronic stress intensity will produce proportional (a gradient or graded) physiological response. We were specifically interested in the timing of the entrance into homeostatic overload, or the start of chronic stress symptoms. To attempt to fill this knowledge gap we split 40 captive house sparrows (Passer domesticus) into four groups (high stress, medium stress, low stress, and a captivity-only control) and subjected them to six bouts of chronic stress over a 6-month period. We varied the number of stressors/day and the length of each individual bout with the goal of producing groups that would experience different magnitudes of wear-and-tear. To evaluate the impact of chronic stress, at the start and end of each stress bout we measured body weight and three plasma metabolites (glucose, ketones, and uric acid) in both a fasted and fed state. All metrics showed significant differences across treatment groups, with the high stress group most frequently showing the greatest changes. However, the changes did not produce a consistent profile that matched the different chronic stress intensities. We also took samples after a prolonged recovery period of 6 weeks after the chronic stressors ended. The only group difference that persisted after 6 weeks was weight—all differences across groups in metabolites recovered. The results indicate that common blood metabolites are sensitive to stressors and may show signs of wear-and-tear, but are not reliable indicators of the intensity of long-term chronic stress. Furthermore, regulatory mechanisms are robust enough to recover within 6 weeks post-stress.

    

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