scholarly journals MicroRNA156 (miR156) Negatively Impacts Mg-Protoporphyrin IX (Mg-Proto IX) Biosynthesis and Its Plastid-Nucleus Retrograde Signaling in Apple

Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 653
Author(s):  
Qingbo Zheng ◽  
Yakun Chen ◽  
Xiaolin Jia ◽  
Yi Wang ◽  
Ting Wu ◽  
...  

Plastid-nucleus retrograde signaling (PNRS) play essential roles in regulating nuclear gene expression during plant growth and development. Excessive reactive oxygen species can trigger PNRS. We previously reported that in apple (Malus domestica Borkh.) seedlings, the expression of microRNA156 (miR156) was significantly low in the adult phase, which was accompanied by high levels of hydrogen peroxide (H2O2) accumulation in chloroplasts. However, it was unclear whether adult-phase-specific chloroplast H2O2 may induce PNRS and affect miR156 expression, or miR156 triggers adult phase PNRS during the ontogenesis. In this paper, we examined the relationship between miR156 levels and six PNRS components in juvenile and adult phase leaves from ‘Zisai Pearl’בRed Fuji’ hybrids. We found that PNRS generated by singlet oxygen (1O2), the photosynthetic redox state, methylerythritol cyclodiphosphate (MEcPP), SAL1-3-phosphoadenosine 5-phosphate (PAP) and WHIRLY1 were not involved. The accumulation of Mg-protoporphyrin IX (Mg-Proto IX), the expression of the synthetic genes MdGUN5 and MdGUN6, and Mg-Proto IX PNRS related nuclear genes increased with ontogenesis. These changes were negatively correlated with miR156 expression. Manipulating Mg-Proto IX synthesis with 5-aminolevulinic acid (ALA) or gabaculine did not affect miR156 expression in vitro shoots. In contrast, modulating miR156 expression via MdGGT1 or MdMIR156a6 transgenesis led to changes in Mg-Proto IX contents and the corresponding gene expressions. It was concluded that the Mg-Proto IX PNRS was regulated downstream of miR156 regardless of adult-phase-specific plastid H2O2 accumulation. The findings may facilitate the understanding of the mechanism of ontogenesis in higher plants.

2021 ◽  
Vol 14 (3) ◽  
pp. 229
Author(s):  
Yo Shinoda ◽  
Daitetsu Kato ◽  
Ryosuke Ando ◽  
Hikaru Endo ◽  
Tsutomu Takahashi ◽  
...  

5-Aminolevulinic acid (5-ALA) is an amino acid derivative and a precursor of protoporphyrin IX (PpIX). The photophysical feature of PpIX is clinically used in photodynamic diagnosis (PDD) and photodynamic therapy (PDT). These clinical applications are potentially based on in vitro cell culture experiments. Thus, conducting a systematic review and meta-analysis of in vitro 5-ALA PDT experiments is meaningful and may provide opportunities to consider future perspectives in this field. We conducted a systematic literature search in PubMed to summarize the in vitro 5-ALA PDT experiments and calculated the effectiveness of 5-ALA PDT for several cancer cell types. In total, 412 articles were identified, and 77 were extracted based on our inclusion criteria. The calculated effectiveness of 5-ALA PDT was statistically analyzed, which revealed a tendency of cancer-classification-dependent sensitivity to 5-ALA PDT, and stomach cancer was significantly more sensitive to 5-ALA PDT compared with cancers of different origins. Based on our analysis, we suggest a standardized in vitro experimental protocol for 5-ALA PDT.


2000 ◽  
Vol 72 (2) ◽  
pp. 186 ◽  
Author(s):  
Saulius Bagdonas ◽  
Li-Wei Ma ◽  
Vladimir Iani ◽  
Ricardas Rotomskis ◽  
Petras Juzenas ◽  
...  

2019 ◽  
Vol 23 (07n08) ◽  
pp. 813-820
Author(s):  
Odrun A. Gederaas ◽  
Harald Husebye ◽  
Anders Johnsson ◽  
Susan Callaghan ◽  
Anders Brunsvik

Aminolevulinic acid and hexyl-aminolevulinate serve as biological precursors to produce photosensitive porphyrins in cells via the heme biosynthetic pathway. This pathway is integral to porphyrin-based photodynamic diagnosis and therapy. By adding exogenous hexyl-aminolevulinate to rat bladder cancer cells (AY27, in vitro) and an animal bladder cancer model (in vivo), fluorescent endogenous porphyrin production was stimulated. Lipophilic protoporphyrin IX was identified as the dominant species by reverse high-pressure liquid chromatography. Subcellular porphyrin localization in the AY27 cells was evaluated by confocal laser scanning microscopy and showed almost quantitative bleaching after 20 s. From this study, we ascertained that the protocol described herein is suitable for hexyl-aminolevulinate-mediated photodynamic therapy and diagnosis when protoporphyrin IX is the active agent.


2007 ◽  
Vol 72 (2) ◽  
pp. 186-192
Author(s):  
Saulius Bagdonas ◽  
Li-Wei Ma ◽  
Vladimir Iani ◽  
Ricardas Rotomskis ◽  
Petras Juzenas ◽  
...  

2016 ◽  
Vol 2 (1) ◽  
Author(s):  
Manti Guha ◽  
Satish Srinivasan ◽  
Kip Guja ◽  
Edison Mejia ◽  
Miguel Garcia-Diaz ◽  
...  

Abstract Reduced mitochondrial DNA copy number, mitochondrial DNA mutations or disruption of electron transfer chain complexes induce mitochondria-to-nucleus retrograde signaling, which induces global change in nuclear gene expression ultimately contributing to various human pathologies including cancer. Recent studies suggest that these mitochondrial changes cause transcriptional reprogramming of nuclear genes although the mechanism of this cross talk remains unclear. Here, we provide evidence that mitochondria-to-nucleus retrograde signaling regulates chromatin acetylation and alters nuclear gene expression through the heterogeneous ribonucleoprotein A2 (hnRNAP2). These processes are reversed when mitochondrial DNA content is restored to near normal cell levels. We show that the mitochondrial stress-induced transcription coactivator hnRNAP2 acetylates Lys 8 of H4 through an intrinsic histone lysine acetyltransferase (KAT) activity with Arg 48 and Arg 50 of hnRNAP2 being essential for acetyl-CoA binding and acetyltransferase activity. H4K8 acetylation at the mitochondrial stress-responsive promoters by hnRNAP2 is essential for transcriptional activation. We found that the previously described mitochondria-to-nucleus retrograde signaling-mediated transformation of C2C12 cells caused an increased expression of genes involved in various oncogenic processes, which is retarded in hnRNAP2 silenced or hnRNAP2 KAT mutant cells. Taken together, these data show that altered gene expression by mitochondria-to-nucleus retrograde signaling involves a novel hnRNAP2-dependent epigenetic mechanism that may have a role in cancer and other pathologies.


2005 ◽  
Vol 40 (1) ◽  
pp. 68-70 ◽  
Author(s):  
Mee Sook Jun ◽  
Hyo-Seon Choi ◽  
Insook Han ◽  
Moonkyu Kim ◽  
Jung Chul Kim

During light-induced chloroplast formation in higher plants the synthesis of several nuclear encoded plastid proteins is under the control of phytochrome. Light acting through the phytochrome system is able both to increase the transcription of certain nuclear genes and to decrease the transcription of others. It has been generally assumed that regulation by phytochrome alone would be sufficient to account for the observed light-dependent changes in nuclear gene expression during chloroplast formation. However, it has recently become evident that the light-dependent control of nuclear gene expression may be far more complex than originally expected. There are at least two other factors that in addition to phytochrome may affect nuclear gene expression: (1) changes in chromatin organization from an inactive to a transcriptionally active state, and (2) a plastid-derived factor that seems to be involved in the transcriptional control of some nuclear genes encoding plastid-specific proteins. Although the light-dependent control of transcription has been studied intensively for nuclear genes, much less is known about the light-dependent control of plastid gene expression. The P700 chlorophyll a protein of photosystem I is a major membrane protein whose massive accumulation is induced by light and whose genes have been located on the plastid DNA. In barley a high concentration of mRNA for the P700 chlorophyll a protein was detected within the total RNA as well as within the polysomal fraction of etioplasts and remained almost constant during greening. Based on these results it can be inferred that the accumulation of the P700 chlorophyll a protein during light-dependent chloroplast development in barley is not coupled to its transcript concentration but is controlled at a translational — or post-translational - level. The possible function of protochlorophyllide as photoreceptor in this light-dependent control of plastid gene expression is discussed.


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