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Rubino, R.

Publications and source records attributed to Rubino, R..

3 recordsLinked to original sources

SELF-PRUNING 5G interplays with age and gibberellin pathways downstream of SlCOL1 to orchestrate photoperiodic tomato flowering

Tomato (Solanum lycopersicum) is classified as a day-neutral plant, whereas its wild relatives exhibit delayed flowering under long day (LD) conditions due to higher activity of the SELF-PRUNING 5G (SP5G). In Arabidopsis thaliana, CONSTANS (CO) activates FLOWERING LOCUS T (FT), a homolog of SP5G, but whether and how CO integrates with SP5G in tomato flowering was unclear. Here, we demonstrate that SlCOL1 (the tomato CO homolog) delays flowering by directly activating SP5G in a PHYTOCHROME B1 (PHYB1)-dependent manner. Importantly, genetic and molecular analyses combining a photoperiod-responsive tomato line carrying the wild SP5G allele from S. pennellii, together with SlCOL1 and flowering-pathway mutants, revealed synergistic crosstalk among the photoperiodic SlCOL1-SP5G module, age-dependent pathway (mediated mainly by the microRNA156-SlSBP module), gibberellin (GA) pathway, and SINGLE FLOWER TRUSS (SFT) pathway. Mechanistically, we show that SP5G forms a complex with miR156-targeted SlSBP13 to directly regulate SFT expression, and that GA may interfere with SP5G activity. Together, these findings revealed a coordinated network that integrates multiple flowering signals to modulate both shared and pathway-specific targets. Our findings provide a significant advance in understanding the molecular regulation of tomato flowering and offer promising avenues for breeding strategies optimized for diverse environmental conditions and latitudes.

plant biology↗

Ketogenic diet promotes tumor ferroptosis but induces relative corticosterone deficiency that accelerates cachexia

The dependency of cancer cells on glucose can be targeted with high-fat low- carbohydrate ketogenic diet (KD). However, hepatic ketogenesis is suppressed in IL-6 producing cancers, which prevents the utilization of this nutrient source as energy for the organism. In two IL-6 associated murine models of cancer cachexia we describe delayed tumor growth but accelerated onset of cancer cachexia and shortened survival when mice are fed KD. Mechanistically, we find this uncoupling is a consequence of the biochemical interaction of two simultaneously occurring NADPH-dependent pathways. Within the tumor, increased production of lipid peroxidation products (LPPs) and, consequently, saturation of the glutathione (GSH) system leads to ferroptotic death of cancer cells. Systemically, redox imbalance and NADPH depletion impairs the biosynthesis of corticosterone, the main regulator of metabolic stress, in the adrenal glands. Administration of dexamethasone, a potent glucocorticoid, improves food intake, normalizes glucose homeostasis and utilization of nutritional substrates, delays onset of cancer cachexia and extends survival of tumor-bearing mice fed KD, while preserving reduced tumor growth. Our study highlights that the outcome of systemic interventions cannot necessarily be extrapolated from the effect on the tumor alone, but that they have to be investigated for anti{-}cancer and host effects. These findings may be relevant to clinical research efforts that investigate nutritional interventions such as KD in patients with cancer. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC="FIGDIR/small/528937v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@613bb6org.highwire.dtl.DTLVardef@19746a4org.highwire.dtl.DTLVardef@9ef652org.highwire.dtl.DTLVardef@3db934_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LIKetogenic diet delays tumor growth but accelerates cancer cachexia and shortens survival C_LIO_LIIn the tumor, accumulation of lipid peroxidation products results in saturation of the GSH detoxifying pathway and ferroptotic death of cancer cells C_LIO_LIIn the host organism, systemic redox state imbalance causes NADPH depletion, GDF-15 elevations, and relative corticosterone deficiency C_LIO_LIDexamethasone coadministration with ketogenic diet delays onset of cancer cachexia by improving food intake, glucose homeostasis and utilization of nutritional substrates C_LI

cancer biology↗

Neurotensin neurons in the central extended amygdala control energy balance

Overeating and a sedentary life style are major causes of obesity and related metabolic disorders. Identification of the neurobiological processes that regulate energy balance will facilitate development of interventions for these disorders. Here we show that the Neurotensin-expressing neurons in the mouse IPAC (IPACNts), a nucleus of the central extended amygdala, bidirectionally coordinate hedonic feeding and physical activity, thereby regulating energy balance, metabolic processes and bodyweight. IPACNts are preferentially activated by consumption of highly palatable food or exposure to its taste and smell. Activating IPACNts promotes food intake in a palatability-dependent manner and decreases locomotion. Conversely, inhibiting IPACNts selectively reduces palatable food intake and dramatically enhances physical activity and energy expenditure, and in parallel stimulates physiological responses that oppose diet-induced obesity and metabolic dysfunctions. Thus, a single neuronal population, Neurotensin-expressing neurons in the IPAC, acts to control obesogenic and leptogenic processes by synergistically coordinating energy intake and expenditure with metabolism.

neuroscience↗