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Aims: The dysregulation of TGF‐β signaling is a crucial pathophysiological process in tumorigenesis and progression. LncRNAs have diverse biological functions and are significant participants in the regulation of tumor signaling pathways. However, the clinical value of lncRNAs related to TGF‐β signaling in glioma is currently unclear. Methods: Data on glioma's RNA‐seq transcriptome, somatic mutation, DNA methylation data, and clinicopathological information were derived from the CGGA and TCGA databases. A prognostic lncRNA signature was constructed by Cox and LASSO regression analyses. TIMER2.0 database was utilized to deduce immune infiltration characteristics. "ELMER v.2" was used to reconstruct TF‐methylation‐gene regulatory network. Immunotherapy and chemotherapy response predictions were implemented by the TIDE algorithm and GDSC database, respectively. In vitro and in vivo experiments were conducted to verify the results and clarify the regulatory mechanism of lncRNA. Results: In glioma, a TGF‐β signaling‐related 15‐lncRNA signature was constructed, including AC010173.1, HOXA‐AS2, AC074286.1, AL592424.1, DRAIC, HOXC13‐AS, AC007938.1, AC010729.1, AC013472.3, AC093895.1, AC131097.4, AL606970.4, HOXC‐AS1, AGAP2‐AS1, and AC002456.1. This signature proved to be a reliable prognostic tool, with high risk indicating an unfavorable prognosis and being linked to malignant clinicopathological and genomic mutation traits. Risk levels were associated with different immune infiltration landscapes, where high risk was indicative of high levels of macrophage infiltration. In addition, high risk also suggested better immunotherapy and chemotherapy response. cg05987823 was an important methylation site in glioma progression, and AP‐1 transcription factor family participated in the regulation of signature lncRNA expression. AGAP2‐AS1 knockdown in in vitro and in vivo experiments inhibited the proliferation, migration, and invasion of glioma cells, as well as the growth of glioma, by downregulating the expression levels of NF‐κB and ERK 1/2 in the TGF‐β signaling pathway. Conclusions: A prognostic lncRNA signature of TGF‐β signaling was established in glioma, which can be used for prognostic judgment, immune infiltration status inference, and immunotherapy response prediction. AGAP2‐AS1 plays an important role in glioma progression. [ABSTRACT FROM AUTHOR]

The light dependence of quantum yields of Photosystem II (Φ) and of CO fixation were determined in C and C plants under atmospheric conditions where photorespiration was minimal. Calculations were made of the apparent quantum yield for CO fixation by dividing the measured rate of photosynthesis by the absorbed light [A/I=Φ and of the true quantum yield by dividing the estimated true rate of photosynthesis by absorbed light [(A+R)/I=Φ·], where R is the rate of respiration in the light. The dependence of the Φ/Φ and Φ/Φ ratios on light intensity was then evaluated. In both C and C plants there was little change in the ratio of Φ/Φ at light intensities equivalent to 10-100% of full sunlight, whereas there was a dramatic increase in the ratio at lower light intensities. Changes in the ratio of Φ/Φ can occur because respiratory losses are not accounted for, due to changes in the partitioning of energy between photosystems or changes in the relationship between PS II activity and CO fixation. The apparent decrease in efficiency of utilization of energy derived from PS II for CO fixation under low light intensity may be due to respiratory loss of CO. Using dark respiration as an estimate of R, the calculated Φ/Φ ratio was nearly constant from full sunlight down to approx 5% of full sunlight, which suggests a strong linkage between the true rate of CO fixation and PS II activity under varying light intensity. Measurements of photosynthesis rates and Φ were made by illuminating upper versus lower leaf surfaces of representative C and C monocots and dicots. With the monocots, the rate of photosynthesis and the ratio of Φ/Φ exhibited a very similar patterns with leaves illuminated from the adaxial versus the abaxial surface, which may be due to uniformity in anatomy and lack of differences in light acclimation between the two surfaces. With dicots, the abaxial surface had both lower rates of photosynthesis and lower Φ values than the adaxial surface which may be due to differences in anatomy (spongy versus palisade mesophyll cells) and/or light acclimation between the two surfaces. However, in each species the response of Φ/Φ to varying light intensity was similar between the two surfaces, indicating a comparable linkage between PS II activity and CO fixation. [ABSTRACT FROM AUTHOR]