Genome Transcriptome Analysis and Functional Characterization of a Nitrogen-Fixation Island in Root-AssociatedPseudomonas stutzeri

The biosynthesis of flavonoids and anthocyanidins has been exclusively investigated in angiosperms but largely unknown in ferns. This study integrated metabolomics and transcriptome to analyze the fronds from different development stages (S1 without spores and S2 with brown spores) of Cyclosorus parasiticus. About 221 flavonoid and anthocyanin metabolites were identified between S1 and S2. Transcriptome analysis revealed several genes encoding the key enzymes involved in the biosynthesis of flavonoids, and anthocyanins were upregulated in S2, which were validated by qRT-PCR. Functional characterization of two chalcone synthases (CpCHS1 and CpCHS2) indicated that CpCHS1 can catalyze the formation of pinocembrin, naringenin, and eriodictyol, respectively; however, CpCHS2 was inactive. The crystallization investigation of CpCHS1 indicated that it has a highly similar conformation and shares a similar general catalytic mechanism to other plants CHSs. And by site-directed mutagenesis, we found seven residues, especially Leu199 and Thr203 that are critical to the catalytic activity for CpCHS1.

Download Full-text

Transcriptome analysis and functional characterization of cerebral organoids in bipolar disorder

Genome Medicine ◽

10.1186/s13073-020-00733-6 ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 10

Author(s):

Annie Kathuria ◽

Kara Lopez-Lengowski ◽

Magdalena Vater ◽

Donna McPhie ◽

Bruce M. Cohen ◽

...

Keyword(s):

Bipolar Disorder ◽

Transcriptome Analysis ◽

Functional Characterization

Download Full-text

Mutagenesis and Functional Characterization of theglnB, glnA, and nifA Genes from the Photosynthetic Bacterium Rhodospirillum rubrum

Journal of Bacteriology ◽

10.1128/jb.182.4.983-992.2000 ◽

2000 ◽

Vol 182 (4) ◽

pp. 983-992 ◽

Cited By ~ 49

Author(s):

Yaoping Zhang ◽

Edward L. Pohlmann ◽

Paul W. Ludden ◽

Gary P. Roberts

Keyword(s):

Nitrogen Fixation ◽

Rhodospirillum Rubrum ◽

Nitrogenase Activity ◽

Functional Characterization ◽

Photosynthetic Bacterium ◽

Wild Type ◽

Adp Ribosylation ◽

Dinitrogenase Reductase ◽

Adp Ribosyltransferase

ABSTRACT Nitrogen fixation is tightly regulated in Rhodospirillum rubrum at two different levels: transcriptional regulation ofnif expression and posttranslational regulation of dinitrogenase reductase by reversible ADP-ribosylation catalyzed by the DRAT-DRAG (dinitrogenase reductase ADP-ribosyltransferase–dinitrogenase reductase-activating glycohydrolase) system. We report here the characterization ofglnB, glnA, and nifA mutants and studies of their relationship to the regulation of nitrogen fixation. Two mutants which affect glnB (structural gene for PII) were constructed. While PII-Y51F showed a lower nitrogenase activity than that of wild type, a PIIdeletion mutant showed very little nif expression. This effect of PII on nif expression is apparently the result of a requirement of PII for NifA activation, whose activity is regulated by NH4 + in R. rubrum. The modification of glutamine synthetase (GS) in theseglnB mutants appears to be similar to that seen in wild type, suggesting that a paralog of PII might exist inR. rubrum and regulate the modification of GS. PII also appears to be involved in the regulation of DRAT activity, since an altered response to NH4 + was found in a mutant expressing PII-Y51F. The adenylylation of GS plays no significant role in nif expression or the ADP-ribosylation of dinitrogenase reductase, since a mutant expressing GS-Y398F showed normal nitrogenase activity and normal modification of dinitrogenase reductase in response to NH4 + and darkness treatments.

Download Full-text

Transcriptome analysis and functional characterization of oxidosqualene cyclases of the arjuna triterpene saponin pathway

Plant Science ◽

10.1016/j.plantsci.2019.110382 ◽

2020 ◽

Vol 292 ◽

pp. 110382 ◽

Cited By ~ 2

Author(s):

Gaurav Srivastava ◽

Sandeep ◽

Anchal Garg ◽

Rajesh Chandra Misra ◽

Chandan Singh Chanotiya ◽

...

Keyword(s):

Transcriptome Analysis ◽

Functional Characterization ◽

Oxidosqualene Cyclases ◽

Triterpene Saponin

Download Full-text

Functional characterization of human brown adipose tissue metabolism

Biochemical Journal ◽

10.1042/bcj20190464 ◽

2020 ◽

Vol 477 (7) ◽

pp. 1261-1286 ◽

Cited By ~ 3

Author(s):

Marie Anne Richard ◽

Hannah Pallubinsky ◽

Denis P. Blondin

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Functional Characterization ◽

Human Infants ◽

Positron Emission ◽

Brown Adipose ◽

Treatment Of Obesity ◽

And Function

Brown adipose tissue (BAT) has long been described according to its histological features as a multilocular, lipid-containing tissue, light brown in color, that is also responsive to the cold and found especially in hibernating mammals and human infants. Its presence in both hibernators and human infants, combined with its function as a heat-generating organ, raised many questions about its role in humans. Early characterizations of the tissue in humans focused on its progressive atrophy with age and its apparent importance for cold-exposed workers. However, the use of positron emission tomography (PET) with the glucose tracer [18F]fluorodeoxyglucose ([18F]FDG) made it possible to begin characterizing the possible function of BAT in adult humans, and whether it could play a role in the prevention or treatment of obesity and type 2 diabetes (T2D). This review focuses on the in vivo functional characterization of human BAT, the methodological approaches applied to examine these features and addresses critical gaps that remain in moving the field forward. Specifically, we describe the anatomical and biomolecular features of human BAT, the modalities and applications of non-invasive tools such as PET and magnetic resonance imaging coupled with spectroscopy (MRI/MRS) to study BAT morphology and function in vivo, and finally describe the functional characteristics of human BAT that have only been possible through the development and application of such tools.

Download Full-text