Leaf status and environmental signals jointly regulate proline metabolism in winter oilseed rape

Abstract Proline metabolism is an essential component of plant adaptation to multiple environmental stress conditions that is also known to participate in specific developmental phases, particularly in reproductive organs. Recent evidence suggested a possible role for proline catabolism in Brassica napus for nitrogen remobilization processes from source leaves at the vegetative stage. Here, we investigate transcript levels of Δ1-PYRROLINE-5-CARBOXYLATE SYNTHASE (P5CS) and PROLINE DEHYDROGENASE (ProDH) genes at the vegetative stage with respect to net proline biosynthesis and degradation fluxes in leaves having a different sink/source balance. We showed that the underexpression of three P5CS1 genes in source leaves was accompanied by a reduced commitment of de novo assimilated 15N towards proline biosynthesis and an overall depletion of free proline content. We found that the expression of ProDH genes was strongly induced by carbon starvation conditions (dark-induced senescence) compared with early senescing leaves. Our results suggested a role for proline catabolism in B. napus, but acting only at a late stage of senescence. In addition, we also identified some P5CS and ProDH genes that were differentially expressed during multiple processes (leaf status, dark to light transition, and stress response).

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Proline metabolism and redox; maintaining a balance in health and disease

Amino Acids ◽

10.1007/s00726-021-03051-2 ◽

2021 ◽

Author(s):

Lisa A. Vettore ◽

Rebecca L. Westbrook ◽

Daniel A. Tennant

Keyword(s):

De Novo ◽

Redox Homeostasis ◽

Protein Structures ◽

Treatment Strategies ◽

Proline Metabolism ◽

Cancer Proliferation ◽

Cellular Redox ◽

Proline Catabolism ◽

Health And Disease ◽

The Impact

AbstractProline is a non-essential amino acid with key roles in protein structure/function and maintenance of cellular redox homeostasis. It is available from dietary sources, generated de novo within cells, and released from protein structures; a noteworthy source being collagen. Its catabolism within cells can generate ATP and reactive oxygen species (ROS). Recent findings suggest that proline biosynthesis and catabolism are essential processes in disease; not only due to the role in new protein synthesis as part of pathogenic processes but also due to the impact of proline metabolism on the wider metabolic network through its significant role in redox homeostasis. This is particularly clear in cancer proliferation and metastatic outgrowth. Nevertheless, the precise identity of the drivers of cellular proline catabolism and biosynthesis, and the overall cost of maintaining appropriate balance is not currently known. In this review, we explore the major drivers of proline availability and consumption at a local and systemic level with a focus on cancer. Unraveling the main factors influencing proline metabolism in normal physiology and disease will shed light on new effective treatment strategies.

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Proline metabolism in cartilage: The importance of proline biosynthesis

Metabolism ◽

10.1016/0026-0495(78)90006-9 ◽

1978 ◽

Vol 27 (6) ◽

pp. 685-694 ◽

Cited By ~ 27

Author(s):

Robert J. Smith ◽

James M. Phang

Keyword(s):

Proline Metabolism ◽

Proline Biosynthesis

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The Non-Essential Amino Acid Cysteine Becomes Essential for Tumor Proliferation and Survival

Cancers ◽

10.3390/cancers11050678 ◽

2019 ◽

Vol 11 (5) ◽

pp. 678 ◽

Cited By ~ 35

Author(s):

Joseph A. Combs ◽

Gina M. DeNicola

Keyword(s):

Amino Acid ◽

Essential Amino Acid ◽

De Novo ◽

Thiol Group ◽

Potential Contribution ◽

Cancer Cell Proliferation ◽

Cellular Processes ◽

Cystine Transporter ◽

Transsulfuration Pathway ◽

Multiple Processes

The non-essential amino acid cysteine is used within cells for multiple processes that rely on the chemistry of its thiol group. Under physiological conditions, many non-transformed tissues rely on glutathione, circulating cysteine, and the de novo cysteine synthesis (transsulfuration) pathway as sources of intracellular cysteine to support cellular processes. In contrast, many cancers require exogeneous cystine for proliferation and viability. Herein, we review how the cystine transporter, xCT, and exogenous cystine fuel cancer cell proliferation and the mechanisms that regulate xCT expression and activity. Further, we discuss the potential contribution of additional sources of cysteine to the cysteine pool and what is known about the essentiality of these processes in cancer cells. Finally, we discuss whether cyst(e)ine dependency and associated metabolic alterations represent therapeutically targetable metabolic vulnerabilities.

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Transcriptome analysis of immature xylem in Chinese fir at different developmental phases

10.7287/peerj.preprints.2032 ◽

2016 ◽

Author(s):

Yunxing Zhang ◽

Xiaojiao Han ◽

Jian Sang ◽

Xuelian he ◽

Mingying Liu ◽

...

Keyword(s):

Transcription Factors ◽

Transcriptome Sequencing ◽

Molecular Mechanisms ◽

De Novo ◽

Southern China ◽

Wood Formation ◽

Chinese Fir ◽

Nac Transcription Factors ◽

Transcriptome Variation ◽

Developmental Phases

Background: Chinese fir [Cunninghamia lanceolata (Lamb .) Hook.], is one of the most important native tree species for timber production in southern China. An understanding of overall fast growing stage, stem growth stage and senescence stage cambium transcriptome variation is lacking. We used transcriptome sequencing to identify the repertoire of genes expressed during development of xylem tissue in Chinese fir, aiming to delineate the molecular mechanisms of wood formation. Results: We carried out transcriptome sequencing at three different cultivation ages (7Y, 15Y and 21Y) generating 68.71 million reads (13.88 Gbp). A total of 140,486 unigenes with a mean size of 568.64 base pairs (bp) were obtained via de novo assembly. Of these, 27,427 unigenes (19.52%) were further annotated by comparison to public protein databases. A total of 5,331 (3.79%) unigenes were mapped into 118 pathways by searching against the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG). Differentially expressed genes (DEG) analysis identified 3, 16 and 5,899 DEGs from the comparison of 7Y vs. 15Y, 7Y vs. 21Y and 15Y vs. 21Y, respectively, in the immature xylem tissues, including 2,638 significantly up-regulated and 3,280 significantly down-regulated genes. Besides, five NAC transcription factors, 190 MYB transcription factors, and 34 WRKY transcription factors were identified respectively from Chinese fir transcriptome. Conclusion: Our results revealed the active transcriptional pathways and identified the DEGs at different cultivation phases of Chinese fir wood formation. This transcriptome dataset will aid in understanding and carrying out future studies on the molecular basis of Chinese fir wood formation and contribute to future artificial production and applications.

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Oncogenic human herpesvirus hijacks proline metabolism for tumorigenesis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1918607117 ◽

2020 ◽

Vol 117 (14) ◽

pp. 8083-8093 ◽

Cited By ~ 5

Author(s):

Un Yung Choi ◽

Jae Jin Lee ◽

Angela Park ◽

Wei Zhu ◽

Hye-Ra Lee ◽

...

Keyword(s):

Cell Culture ◽

Cell Growth ◽

Tumor Cell ◽

Kaposi's Sarcoma ◽

3D Culture ◽

Tumor Cell Growth ◽

Proline Metabolism ◽

Proline Biosynthesis

Three-dimensional (3D) cell culture is well documented to regain intrinsic metabolic properties and to better mimic the in vivo situation than two-dimensional (2D) cell culture. Particularly, proline metabolism is critical for tumorigenesis since pyrroline-5-carboxylate (P5C) reductase (PYCR/P5CR) is highly expressed in various tumors and its enzymatic activity is essential for in vitro 3D tumor cell growth and in vivo tumorigenesis. PYCR converts the P5C intermediate to proline as a biosynthesis pathway, whereas proline dehydrogenase (PRODH) breaks down proline to P5C as a degradation pathway. Intriguingly, expressions of proline biosynthesisPYCRgene and proline degradationPRODHgene are up-regulated directly by c-Myc oncoprotein and p53 tumor suppressor, respectively, suggesting that the proline-P5C metabolic axis is a key checkpoint for tumor cell growth. Here, we report a metabolic reprogramming of 3D tumor cell growth by oncogenic Kaposi’s sarcoma-associated herpesvirus (KSHV), an etiological agent of Kaposi’s sarcoma and primary effusion lymphoma. Metabolomic analyses revealed that KSHV infection increased nonessential amino acid metabolites, specifically proline, in 3D culture, not in 2D culture. Strikingly, the KSHV K1 oncoprotein interacted with and activated PYCR enzyme, increasing intracellular proline concentration. Consequently, the K1-PYCR interaction promoted tumor cell growth in 3D spheroid culture and tumorigenesis in nude mice. In contrast, depletion ofPYCRexpression markedly abrogated K1-induced tumor cell growth in 3D culture, not in 2D culture. This study demonstrates that an increase of proline biosynthesis induced by K1-PYCR interaction is critical for KSHV-mediated transformation in in vitro 3D culture condition and in vivo tumorigenesis.

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Expression of Campylobacter genes for proline biosynthesis in Escherichia coli

Canadian Journal of Microbiology ◽

10.1139/m85-201 ◽

1985 ◽

Vol 31 (11) ◽

pp. 1064-1067 ◽

Cited By ~ 5

Author(s):

Eileen C. Lee ◽

Richard I. Walker ◽

Patricia Guerry

Keyword(s):

Escherichia Coli ◽

Salmonella Typhimurium ◽

Campylobacter Jejuni ◽

Proline Metabolism ◽

Proline Biosynthesis ◽

E Coli

Cloned DNA from Campylobacter jejuni was found to complement auxotrophic defects in proline metabolism in several strains of Escherichia coli. A 4.4-kilobase fragment of Campylobacter DNA encodes the genes analogous to the proA and B genes of E. coli and Salmonella typhimurium.

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Environmental cues induce a long noncoding RNA–dependent remodeling of the nucleolus

Molecular Biology of the Cell ◽

10.1091/mbc.e13-04-0223 ◽

2013 ◽

Vol 24 (18) ◽

pp. 2943-2953 ◽

Cited By ~ 56

Author(s):

Mathieu D. Jacob ◽

Timothy E. Audas ◽

James Uniacke ◽

Laura Trinkle-Mulcahy ◽

Stephen Lee

Keyword(s):

Long Noncoding Rna ◽

Noncoding Rna ◽

De Novo ◽

Intergenic Spacer ◽

Structure And Function ◽

Functional Adaptation ◽

Distinct Region ◽

Environmental Signals ◽

Mammalian Cell Lines ◽

And Function

The nucleolus is a plurifunctional organelle in which structure and function are intimately linked. Its structural plasticity has long been appreciated, particularly in response to transcriptional inhibition and other cellular stresses, although the mechanism and physiological relevance of these phenomena are unclear. Using MCF-7 and other mammalian cell lines, we describe a structural and functional adaptation of the nucleolus, triggered by heat shock or physiological acidosis, that depends on the expression of ribosomal intergenic spacer long noncoding RNA (IGS lncRNA). At the heart of this process is the de novo formation of a large subnucleolar structure, termed the detention center (DC). The DC is a spatially and dynamically distinct region, characterized by an 8-anilino-1-naphthalenesulfonate–positive hydrophobic signature. Its formation is accompanied by redistribution of nucleolar factors and arrest in ribosomal biogenesis. Silencing of regulatory IGS lncRNA prevents the creation of this structure and allows the nucleolus to retain its tripartite organization and transcriptional activity. Signal termination causes a decrease in IGS transcript levels and a return to the active nucleolar conformation. We propose that the induction of IGS lncRNA by environmental signals operates as a molecular switch that regulates the structure and function of the nucleolus.

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Female maturation and rematuration acceleration of Mutiara strain catfish (Clarias gariepinus) using combination of oocyte developer hormone and astaxanthin addition diet

Jurnal Akuakultur Indonesia ◽

10.19027/jai.18.1.23-32 ◽

2019 ◽

Vol 18 (1) ◽

pp. 23-32

Author(s):

Fatahillah Maulana Jufri ◽

Agus Oman Sudrajat ◽

Mia Setiawati

Keyword(s):

Clarias Gariepinus ◽

Reproductive Organs ◽

African Catfish ◽

North African ◽

Environmental Signals ◽

Gonadal Maturation ◽

Gonadal Maturity ◽

Research Designs ◽

Broodstock Diet ◽

Female Maturation

ABSTRACT Reproductive design for gonadal maturation process mostly related with some factors such as environmental signals, reproductive organs, hormonal and nutrition. This research was conducted on female Mutiara strain of North African Catfish, Clarias gariepinus by combining two kinds of materials administered to broodstock diet, namely oocyte developer (Oodev) which contains of PMSG hormone and antidopamin, and astaxanthin carotenoid. Research designs were divided into C (Control), A50 (astaxanthin 50 mg/kg feed), A100 (astaxanthin 100 mg/kg feed), Od0.5 (Oodev 0.5 mL/kg fish for two weeks), Od1 (1 mL/kg fish for 2 weeks), Od0.5A50 (combined Od0.5 with A50), Od1A50 (combined Od1 with A50), Od0.5A100 (combined Od0.5 with A100), and Od1A100 (combined Od1 with A100). This research was performed during twelve weeks of feeding. The Od1A100 treatment showed the best reproduction performance result compared to other treatment with highest hepatosomatic (HSI) and gonadosomatic (HSI) indexes (P<0.05), also fastest increase in egg diameters (P<0.05), shorter rematuration periods and highest proportion of mature broodstock. These results indicated that Oodev and astaxanthin could accelerate gonadal maturity in female broodstock of Mutiara catfish.Keywords: Broodstock, hormonal, reproduction, oocyte developer, astaxanthin ABSTRAK Rekayasa reproduksi untuk proses pematangan gonad sebagian besar terkait dengan beberapa faktor seperti sinyal lingkungan, organ reproduksi, hormonal dan nutrisi. Penelitian ini dilakukan terhadap strain ikan lele Mutiara (Clarias gariepinus) betina menggunakan dua bahan yang dicampur pada pakan induk, yaitu oocyte developer (Oodev) yang mengandung hormon PMSG dan antidopamin, dan karotenoid astaxanthin. Eksperimen yang dirancang adalah K (Kontrol), A50 (Astaxanthin 50 mg/kg pakan), A100 (Astaxanthin 100 mg/kg pakan), Od0.5 (Oodev 0,5 mL/kg induk untuk 2 minggu), Od1 (Oodev 1 mL/kg induk untuk 2 minggu), Od0.5A50 (kombinasi Od0.5 dan A50), Od1A50 (kombinasi Od1 dan A50), Od0.5A100 (kombinasi Od0.5 dan A100), dan Od1A100 (kombinasi Od1 dan A100). Penelitian ini dilakukan dengan memberi makan dua belas minggu. Performa reproduksi terbaik didapat pada perlakuan Od1A100. Od1A100 memiliki indeks hepatosomatik (HSI) dan gonadosomatik (HSI) tertinggi (P <0,05), juga diameter telur paling cepat besar (p <0,05), periode rematurasi terpendek, dan proporsi induk matang gonad tertinggi. Hasil ini menunjukkan bahwa Oodev dan astaxanthin dapat mempercepat kematangan gonad pada induk betina ikah lele Mutiara. Keyword: Induk, hormon, reproduksi, oocyte developer, astaxanthin

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Global reinforcement of DNA methylation through enhancement of RNA-directed DNA methylation ensures sexual reproduction in rice

10.1101/2020.07.02.185371 ◽

2020 ◽

Author(s):

Lili Wang ◽

Longjun Zeng ◽

Kezhi Zheng ◽

Tianxin Zhu ◽

Yumeng Yin ◽

...

Keyword(s):

Dna Methylation ◽

Sexual Reproduction ◽

De Novo ◽

Rice Genome ◽

Biological Significance ◽

Reproductive Organs ◽

Epigenetic Mark ◽

Small Interfering Rnas ◽

Genome Wide ◽

Global Increase

AbstractDNA methylation is an important epigenetic mark that regulates the expression of genes and transposons. RNA-directed DNA methylation (RdDM) is the main molecular pathway responsible for de novo DNA methylation in plants. In Arabidopsis, however, mutations in RdDM genes cause no visible developmental defects, which raising the question of the biological significance of RdDM in plant development. Here, we isolated and cloned Five Elements Mountain 1 (FEM1), which encodes an RNA-dependent RNA polymerase. Mutation in FEM1 substantially decreased genome-wide CHH methylation levels and abolished the accumulation of 24-nt small interfering RNAs. Moreover, male and female reproductive development was disturbed, which led to the sterility of fem1 mutants. In wild-type (WT) plants but not in fem1 mutants, genome-wide CHH DNA methylation levels were greater in panicles, stamens, and pistils than in seedlings. The global increase of methylation in reproductive organs of the WT was attributed to enhancement of RdDM activity including FEM1 activity. More than half of all encoding genes in the rice genome overlapped with hypermethylated regions in the sexual organs of the WT, and many of them appear to be directly regulated by an increase in DNA methylation.Our results demonstrate that a global increase of DNA methylation through enhancement of RdDM activity in reproductive organs ensures sexual reproduction of rice.

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Expression Patterns of DNA Methylation and Demethylation Genes during Plant Development and in Response to Phytohormones

International Journal of Molecular Sciences ◽

10.3390/ijms22189681 ◽

2021 ◽

Vol 22 (18) ◽

pp. 9681

Author(s):

Morgan Bennett ◽

Kailyn Cleaves ◽

Tarek Hewezi

Keyword(s):

Dna Methylation ◽

Plant Development ◽

Promoter Activity ◽

De Novo ◽

Expression Profiles ◽

Expression Patterns ◽

Methylation Status ◽

Reproductive Organs ◽

Highly Active ◽

Root Tissues

DNA methylation and demethylation precisely and effectively modulate gene expression during plant growth and development and in response to stress. However, expression profiles of genes involved in DNA methylation and demethylation during plant development and their responses to phytohormone treatments remain largely unknown. We characterized the spatiotemporal expression patterns of genes involved in de novo methylation, methyl maintenance, and active demethylation in roots, shoots, and reproductive organs using β-glucuronidase (GUS) reporter lines. Promoters of DNA demethylases were generally more highly active at the mature root tissues, whereas the promoters of genes involved in DNA methylation were more highly active at fast-growing root tissues. The promoter activity also implies that methylation status in shoot apex, leaf primordia, floral organs, and developing embryos is under tight equilibrium through the activity of genes involved in DNA methylation and demethylation. The promoter activity of DNA methylation and demethylation-related genes in response to various phytohormone treatments revealed that phytohormones can alter DNA methylation status in specific and redundant ways. Overall, our results illustrate that DNA methylation and demethylation pathways act synergistically and antagonistically in various tissues and in response to phytohormone treatments and point to the existence of hormone-linked methylome regulation mechanisms that may contribute to tissue differentiation and development.

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