We provide a functional characterization of transcription factor NF-κB in protists and provide information about the evolution and diversification of this biologically important protein. We characterized NF-κB in two protists using phylogenetic, cellular, and biochemical techniques. NF-κB of the holozoan
We demonstrate two synthetic single-cell systems that can be used to better understand how the acquisition of an orphan gene can affect complex phenotypes. The Arabidopsis orphan gene,
- Award ID(s):
- 2238942
- NSF-PAR ID:
- 10488023
- Publisher / Repository:
- Frontiers
- Date Published:
- Journal Name:
- Frontiers in Plant Science
- Volume:
- 14
- ISSN:
- 1664-462X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Capsaspora owczarzaki (Co ) has an N-terminal DNA-binding domain and a C-terminal Ankyrin repeat (ANK) domain, and its DNA-binding specificity is more similar to metazoan NF-κB proteins than to Rel proteins. Removal of the ANK domain allowsCo -NF-κB to enter the nucleus, bind DNA, and activate transcription. However, C-terminal processing ofCo -NF-κB is not induced by IκB kinases in human cells. OverexpressedCo -NF-κB localizes to the cytoplasm inCo cells.Co -NF-κB mRNA and DNA-binding levels differ across threeCapsaspora life stages. RNA-sequencing and GO analyses identify possible gene targets ofCo -NF-κB. Three NF-κB-like proteins from the choanoflagellateAcanthoeca spectabilis (As ) contain conserved Rel Homology domain sequences, but lack C-terminal ANK repeats. All threeAs -NF-κB proteins constitutively enter the nucleus of cells, but differ in their DNA-binding abilities, transcriptional activation activities, and dimerization properties. These results provide a basis for understanding the evolutionary origins of this key transcription factor and could have implications for the origins of regulated immunity in higher taxa. -
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Arabidopsis thaliana , namedQUA‐QUINE STARCH (QQS ) is involved in the metabolic processes for partitioning of carbon and nitrogen among proteins and carbohydrates, thus influencing leaf, seed composition, and plant defense in Arabidopsis. In this study, we show that PHYTOCHROME‐INTERACTING bHLH TRANSCRIPTION FACTORS (PIFs), including PIF4, are required to suppressQQS during the period at dawn, thus preventing overconsumption of starch reserves.QQS expression is significantly de‐repressed inpif4 andpifQ , while repressed by overexpression ofPIF4 , suggesting that PIF4 and its close homologs (PIF1, PIF3, and PIF5) act as negative regulators ofQQS expression. In addition, we show that the evening complex, including ELF3 is required for active expression ofQQS , thus playing a positive role in starch catabolism during night‐time. Furthermore,QQS is epigenetically suppressed by DNA methylation machinery, whereas histone H3 K4 methyltransferases (e.g., ATX1, ATX2, and ATXR7) and H3 acetyltransferases (e.g., HAC1 and HAC5) are involved in the expression ofQQS . This study demonstrates that PIF light signaling factors help plants utilize optimal amounts of starch during the night and prevent overconsumption of starch before its biosynthesis during the upcoming day. -
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Abstract To identify protein–protein interactions and phosphorylated amino acid sites in eukaryotic mRNA translation, replicate TAP‐MudPIT and control experiments are performed targeting
Saccharomyces cerevisiae genes previously implicated in eukaryotic mRNA translation by their genetic and/or functional roles in translation initiation, elongation, termination, or interactions with ribosomal complexes. Replicate tandem affinity purifications of each targeted yeast TAP‐tagged mRNA translation protein coupled with multidimensional liquid chromatography and tandem mass spectrometry analysis are used to identify and quantify copurifying proteins. To improve sensitivity and minimize spurious, nonspecific interactions, a novel cross‐validation approach is employed to identify the most statistically significant protein–protein interactions. Using experimental and computational strategies discussed herein, the previously described protein composition of the canonical eukaryotic mRNA translation initiation, elongation, and termination complexes is calculated. In addition, statistically significant unpublished protein interactions and phosphorylation sites forS. cerevisiae ’s mRNA translation proteins and complexes are identified. -
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Lack of proper nutrition has important consequences for the physiology of all organisms, and nutritional status can affect immunity, based on many studies in terrestrial animals. Here we show a positive correlation between nutrition and immunity in the sea anemonemore » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/fpls.2023.1126139
