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1. L eg M uscle A rchitecture in P rimates and I ts C orrelation with L ocomotion P atterns

   https://doi.org/10.1002/ar.23745  

   Marchi, Damiano; Leischner, Carissa L; Pastor, Francisco; Hartstone‐Rose, Adam (March 2018, The Anatomical Record)

   ABSTRACT Bone biomechanical studies indicate that leg bone structure can be related to different locomotor patterns. The osteological correlates of extant primates’ locomotion patterns and substrate use are important to consider when estimating corresponding behaviors of extinct primates. Here, we test if these same patterns are seen in the differences in leg muscular architecture. Muscle mass, fascicle lengths (FL), physiological cross‐sectional area (PCSA), reduced PCSA (RPCSA) and tendon‐to‐muscle belly ratio were studied in 33 primate species (6 strepsirrhines, 14 platyrrhines and 13 catarrhines). Muscles were grouped into toe and ankle flexors and extensors and studied for phylogenetic and functional signals. All variables strongly correlate with body mass: strength variables (mass, PCSA and RPCSA) scale with positive allometry, whereas the speed/stretch measure (FL) trend toward negative allometry. Thus, larger primates are relatively stronger than smaller species, but they have relatively shorter leg muscle fibers than smaller primates. The strongest functional signal emerged when comparing belly‐muscle tendon unit (MTU) length ratio in leaping and non‐leaping primates. Leapers show significantly smaller plantarflexor belly‐MTU ratio. Surprisingly, no significant results reflect a correlation between muscle architecture and substrate and locomotor groups. However, several trends suggest that a larger sample and more fine‐grained defined categories could produce significant results. These results show the complex relation between leg bone biomechanics and muscle architecture and demand for further studies on this topic. Anat Rec, 301:515–527, 2018. © 2018 Wiley Periodicals, Inc. 

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2. HAIRY MERISTEM proteins regulate the WUSCHEL protein levels in mediating CLAVATA3 expression

   https://doi.org/10.1111/ppl.14505  

   Rodriguez, Kevin; Kao, Lloyd; Cerbantez‐Bueno, Vincent E; Delgadillo, Christian; Nguyen, Dorothy; Ullah, Samin; Delgadillo, Cameron; Reddy, G Venugopala (September 2024, Physiologia Plantarum)

   Abstract The precise regulation of stem cells in the shoot apical meristems (SAMs) involves the function of the homeodomain transcription factor (TF)‐WUSCHEL (WUS). WUS has been shown to move from the site of production‐the rib‐meristem (RM), into overlaying cells of the central zone (CZ), where it specifies stem cells and also regulates the transcription ofCLAVATA3 (CLV3). The secreted signalling peptide CLV3 activates a receptor kinase signalling that restrictsWUStranscription and also regulates the nuclear gradient of WUS by offsetting nuclear export. WUS has been shown to regulate bothCLV3levels and spatial activation, restricting its expression to a few cells in the CZ. The HAIRY MERISTEM (HAM), a GRASS‐domain class of TFs expressed in the RM, has been shown to physically interact with WUS and regulateCLV3expression. However, the mechanisms by which this interaction regulatesCLV3expression non‐cell autonomously remain unclear. Here, we show that HAM function is required for regulating the WUS protein stability, and theCLV3expression responds to altered WUS protein levels inhammutants. Thus, HAM proteins non‐cell autonomously regulatesCLV3expression. 

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3. The changes in plant and soil C pools and their C : N stoichiometry control grassland N retention under elevated N inputs

   https://doi.org/10.1002/eap.2517  

   Yang, Sen; Liu, Weixing; Guo, Lulu; Wang, Chengzhang; Deng, Meifeng; Peng, Ziyang; Liu, Lingli (March 2022, Ecological Applications)
4. Manganese‐dependent transcription regulation by MntR and PerR in Thermus thermophilus HB8

   https://doi.org/10.1111/mmi.15278  

   Barrows, John K; Stubbs, Kamya A; Padilla‐Montoya, Irina F; Leeper, Thomas C; Van Dyke, Michael W (May 2024, Molecular Microbiology)

   Abstract Bacteria contain conserved mechanisms to control the intracellular levels of metal ions. Metalloregulatory transcription factors bind metal cations and play a central role in regulating gene expression of metal transporters. Often, these transcription factors regulate transcription by binding to a specific DNA sequence in the promoter region of target genes. Understanding the preferred DNA‐binding sequence for transcriptional regulators can help uncover novel gene targets and provide insight into the biological role of the transcription factor in the host organism. Here, we identify consensus DNA‐binding sequences and subsequent transcription regulatory networks for two metalloregulators from the ferric uptake regulator (FUR) and diphtheria toxin repressor (DtxR) superfamilies inThermus thermophilusHB8. By homology search, we classify the DtxR homolog as a manganese‐specific, MntR (TtMntR), and the FUR homolog as a peroxide‐sensing, PerR (TtPerR). Both transcription factors repress separate ZIP transporter genes in vivo, andTtPerR acts as a bifunctional transcription regulator by activating the expression of ferric and hemin transport systems. We showTtPerR andTtMntR bind DNA in the presence of manganese in vitro and in vivo; however,TtPerR is unable to bind DNA in the presence of iron, likely due to iron‐mediated histidine oxidation. Unlike canonical PerR homologs,TtPerR does not appear to contribute to peroxide detoxification. Instead, theTtPerR regulon and DNA binding sequence are more reminiscent of Fur or Mur homologs. Collectively, these results highlight the similarities and differences between two metalloregulatory superfamilies and underscore the interplay of manganese and iron in transcription factor regulation. 

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5. 24R ,25( OH ) ₂D₃ regulates tumorigenesis in estrogen sensitive laryngeal cancer cells via membrane‐associated receptor complexes in ER + and ER− cells

   https://doi.org/10.1002/ijc.70141  

   Dennis, Cydney D; Cohen, D Joshua; Debnath, Kusal; Schwartz, Nofrat; Lodato, Brock P; Dillon, Jonathan T; Batool, Tillat; Halquist, Matthew S; Ghosh, Preetam; Schwartz, Zvi; et al (September 2025, International Journal of Cancer)

   Abstract This study examined the effects of 24R,25‐dihydroxyvitamin D₃(24R,25(OH)₂D₃) in estrogen‐responsive laryngeal cancer tumorigenesis in vivo, the mechanisms involved, and whether the ability of the tumor cells to produce 24R,25(OH)₂D₃locally is estrogen‐dependent. Estrogen receptor alpha‐66 positive (ER+) UM‐SCC‐12 cells and ER− UM‐SCC‐11A cells responded differently to 24R,25(OH)₂D₃in vivo; 24R,25(OH)₂D₃enhanced tumorigenesis in ER+ tumors but inhibited tumorigenesis in ER− tumors. Treatment with 17β‐estradiol (E₂) for 24 h reduced levels of CYP24A1 protein but increased 24R,25(OH)₂D₃production in ER+ cells; treatment with E₂for 9 min reduced CYP24A1 at 24 h and reduced 24R,25(OH)₂D₃production in ER− cells. These findings suggest the involvement of E₂receptor(s) in addition to ERα66. To investigate if 24R,25(OH)₂D₃can act locally, ER+ and ER− cells were treated with 24R,25(OH)₂D₃after inhibiting putative 24R,25(OH)₂D₃receptors, and the cells were assessed for effects on DNA synthesis (proliferation) and p53 production (apoptosis). Specific inhibitors were used to assess downstream secondary messenger signaling pathways and requirements for palmitoylation and caveolae in both cell lines. The results show that 24R,25(OH)₂D₃binds to a complex of receptors, including TLCD3B2, VDR, and protein disulfide‐isomerase A3 (PDIA3) in ER+ UM‐SCC‐12 cells. The mechanism requires palmitoylation, and PLD, PI3K, and LPAR are involved. The anti‐tumorigenic effects of 24R,25(OH)₂D₃in ER− UM‐SCC‐11A cells involve a membrane‐receptor complex consisting of VDR, PDIA3, and ROR2 within caveolae to activate a yet‐to‐be‐elucidated downstream signaling cascade. This work demonstrates a driving mechanism for the therapeutic agent 24R,25(OH)₂D₃that may be used for laryngeal cancer patients. 

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