Physiological Precursor Research Articles

Eliciting a single amino acid change by vaccination generates antibody protection against group 1 and group 2 influenza A viruses

Broadly neutralizing antibodies (bnAbs) targeting the hemagglutinin (HA) stem of influenza A viruses (IAVs) tend to be effective against either group 1 or group 2 viral diversity. In rarer cases, intergroup protective bnAbs can be generated by human antibody paratopes that accommodate the conserved glycan differences between the group 1 and group 2 stems. We applied germline-engaging nanoparticle immunogens to elicit a class of cross-group bnAbs from physiological precursor frequency within a humanized mouse model. Cross-group protection depended on the presence of the human bnAb precursors within the B cell repertoire, and the vaccine-expanded antibodies enriched for an N55T substitution in the CDRH2 loop, a hallmark of the bnAb class. Structurally, this single mutation introduced a flexible fulcrum to accommodate glycosylation differences and could alone enable cross-group protection. Thus, broad IAV immunity can be expanded from the germline repertoire via minimal antigenic input and an exceptionally simple antibody development pathway.

Erratum to: Improvement in Quality and Yield of Mungbean Through Combined Use of Crop-Specific Rhizobium and Physiological Precursors

Erratum to: Improvement in Quality and Yield of Mungbean Through Combined Use of Crop-Specific Rhizobium and Physiological Precursors

Effect of varying concentrations of Tryptamine on the development of Zea Mays

Rhizobium is a widely acknowledged bacterium due to its symbiotic relationship, particularly with leguminous forages. It forms nodules, a specialized structure, in approximately 90% of the Fabaceae family and exhibits various methods to enhance soil fertility. Rhizobium can form a symbiotic relationship with non-leguminous plants due to its exceptional colonization abilities, which can contribute to enhanced crop growth. Physiological precursors are utilized in conjunction with rhizobium due to their superior water solubility, consistent hormone supply, and cost-effectiveness. The aim of this investigation was to assess the impact of precursor, both with and without Tryptamine, on the growth parameters of maize. A total of six treatments consisting of tryptamine dilutions were planned for the experiment. The findings indicate that Tryptamine @ 10-4 (T5) resulted in the greatest shoot length (43.6 cm), fresh weight (11.78 g) and dry weight (1.67 g), root length (36 cm), fresh weight (4.91 g) and dry weight (1.99 g), as well as chlorophyll (a) and (b) levels (1.05 and 0.77 mg g-1). The efficacy of precursor application has been determined and warrants further examination in diverse ecologies.

Condensation of the β-cell secretory granule luminal cargoes pro/insulin and ICA512 RESP18 homology domain.

ICA512/PTPRN is a receptor tyrosine-like phosphatase implicated in the biogenesis and turnover of the insulin secretory granules (SGs) in pancreatic islet beta cells. Previously we found biophysical evidence that its luminal RESP18 homology domain (RESP18HD) forms a biomolecular condensate and interacts with insulin in vitro at close-to-neutral pH, that is, in conditions resembling those present in the early secretory pathway. Here we provide further evidence for the relevance of these findings by showing that at pH 6.8 RESP18HD interacts also with proinsulin-the physiological insulin precursor found in the early secretory pathway and the major luminal cargo of β-cell nascent SGs. Our light scattering analyses indicate that RESP18HD and proinsulin, but also insulin, populate nanocondensates ranging in size from 15 to 300 nm and 10e2 to 10e6 molecules. Co-condensation of RESP18HD with proinsulin/insulin transforms the initial nanocondensates into microcondensates (size >1 μm). The intrinsic tendency of proinsulin to self-condensate implies that, in the ER, a chaperoning mechanism must arrest its spontaneous intermolecular condensation to allow for proper intramolecular folding. These data further suggest that proinsulin is an early driver of insulin SG biogenesis, in a process in which its co-condensation with RESP18HD participates in their phase separation from other secretory proteins in transit through the same compartments but destined to other routes. Through the cytosolic tail of ICA512, proinsulin co-condensation with RESP18HD may further orchestrate the recruitment of cytosolic factors involved in membrane budding and fission of transport vesicles and nascent SGs.

A synopsis of wearable commercially available biometric‐monitoring devices and their potential applications during gallop racing

SummaryAmidst discourse surrounding the racing industry's social licence to operate, the welfare of racehorses and jockeys is often at the forefront of discussions. Specifically, catastrophic events and the sudden death of horses on race days tend to capture media attention and often place the racing industry under public scrutiny. While such occurrences are not frequent, they have negative ramifications on the welfare of both racehorses and jockeys. The development and application of advanced monitoring technology could provide greater insight into the physiological precursors that immediately precede sudden death on race days and enable retrospective analyses of catastrophic events that take place. Most importantly, the application of such technology could ultimately aid racetrack personnel in identifying and intervening with horses at increased risk of catastrophic events, right up until the start of a race. This would inevitably improve the safety and welfare of horses and jockeys. Thus, the current review details key cardiovascular, respiratory and thermometry biometrics for racehorses and examines the currently available commercial devices with potential applications during racing. This review also highlights the importance of gathering biometric data for retrospective analyses of catastrophic events and their implications on the welfare of racehorses and jockeys.

Improvement in Quality and Yield of Mungbean Through Combined Use of Crop-Specific Rhizobium and Physiological Precursors

Improvement in Quality and Yield of Mungbean Through Combined Use of Crop-Specific Rhizobium and Physiological Precursors

Identification of an FXR-modulated liver-intestine hybrid state in iPSC-derived hepatocyte-like cells.

Pluripotent stem cell (PSC)-derived hepatocyte-like cells (HLC) have enormous potential as a replacement for primary hepatocytes in drug screening, toxicology and cell replacement therapy, but their genome-wide expression patterns differ strongly from primary human hepatocytes (PHH). We differentiated human induced pluripotent stem cells (hiPSC) via definitive endoderm to HLC and characterized the cells by single-cell and bulk RNA-seq, with complementary epigenetic analyses. We then compared HLC to PHH and publicly available data on human fetal hepatocytes (FH) exvivo; we performed bioinformatics-guided interventions to improve HLC differentiation via lentiviral transduction of the nuclear receptor FXR and agonist exposure. Single-cell RNA-seq revealed that transcriptomes of individual HLC display a hybrid state, where hepatocyte-associated genes are expressed in concert with genes that are not expressed in PHH - mostly intestinal genes - within the same cell. Bulk-level overrepresentation analysis, as well as regulon analysis at the single-cell level, identified sets of regulatory factors discriminating HLC, FH, and PHH, hinting at a central role for the nuclear receptor FXR in the functional maturation of HLC. Combined FXR expression plus agonist exposure enhanced the expression of hepatocyte-associated genes and increased the ability of bile canalicular secretion as well as lipid droplet formation, thereby increasing HLCs' similarity to PHH. The undesired non-liver gene expression was reproducibly decreased, although only by a moderate degree. In contrast to physiological hepatocyte precursor cells and mature hepatocytes, HLC co-express liver and hybrid genes in the same cell. Targeted modification of the FXR gene regulatory network improves their differentiation by suppressing intestinal traits whilst inducing hepatocyte features. Generation of human hepatocytes from stem cells represents an active research field but its success is hampered by the fact that the stem cell-derived 'hepatocytes' still show major differences to hepatocytes obtained from a liver. Here, we identified an important reason for the difference, specifically that the stem cell-derived 'hepatocyte' represents a hybrid cell with features of hepatocytes and intestinal cells. We show that a specific protein (FXR) suppresses intestinal and induces liver features, thus bringing the stem cell-derived cells closer to hepatocytes derived from human livers.

An ideographic study into physiology, alcohol craving and lapses during one hundred days of daily life monitoring

IntroductionAlcohol craving is a highly challenging obstacle to achieve long-term abstinence. Making alcohol use disorder patients timely aware of high-risk craving situations may protect them against relapse by prompting them to mobilize their coping resources. Current advances in wearable and smart-phone technology provide novel opportunities for the development of detecting these situations of heightened risk of craving, by enabling continuous tracking of fluctuations in psychological and physiological parameters. The present study therefore aims to determine the association between self-reported craving and relapses, and between heightened physiological activity. Specifically, we measured cardiovascular and electrodermal activity, and self-reported craving during one hundred days in the daily life of people trying to recover from alcoholism. The secondary aim is to study whether the association between physiology and craving can be strengthened by the inclusion of context related psychological parameters. MethodsAn intensive repeated and continuous measures in naturalistic settings case-study design was employed. Ten participants were monitored with wearable bio-sensors and answered multiple questions every three hours on a smartphone app about craving, lapsing and multiple evidence based contextual variables. The association between physiology, craving and lapses was explored using Matthews correlation coefficients both with a current and 3 h lagged design. The contextual variables were included in a decision tree together with the physiological parameters to explore the added effect on the correlation of these contextual variables. ResultsThe association between lapses and craving was highly different across individuals, varying between a weak to a strong association. The association between cardiovascular activity and heightened self-reported craving was negligible to weak, however with a high specificity, meaning that most craving events were accompanied by increase heart rate. However, the association between electrodermal activity and craving was lower than with cardiovascular activity for most participants, both prior (lagged) and during craving. For two of the participants the association between physiology and craving improved by adding contextual variables, however, precision was too low. ConclusionsPeople differ strongly in their bodily reactions and psychological experiences during the first months of their addiction treatment. No individual in our study had unique one-to-one mappings between on the one hand physiological or psychological precursors, and on the other hand craving and (re)lapses. Therefore, detecting high risk craving situations with both physiological activity measured with wearables and psychological precursors to alert people specifically for an imminent (re)lapse, does not seem viable on the basis of the current results. We do see an added benefit of using physiology during treatment, as physiology can help start the conversation about possible high risk craving situations during that week. This would also help the counselor to gain added insights into the fluctuating states of the clients, and help to ameliorate the recall bias of clients. The present study showed the possibility and paved the way for future intensive longitudinal designs integrating both physiological, psychological and contextual factors during the challenging and lengthy recovery from addiction.

Nitric oxide protects against cochlear hair cell damage and noise-induced hearing loss through glucose metabolic reprogramming

Nitric oxide (NO) is critically involved in the regulation of a wide variety of physiological and pathophysiological processes. However, the role of NO in the pathogenesis of noise-induced hearing loss (NIHL) is complex and remains controversial. Here we reported that treatment of CBA/J mice with l-arginine, a physiological precursor of NO, significantly reduced noise-induced reactive oxygen species accumulation in outer hair cells (OHCs), attenuated noise-induced loss of OHCs and NIHL consequently. Conversely, pharmacological inhibition of endothelial nitric oxide synthase exacerbated noise-induced loss of OHCs and aggravated NIHL. In HEI-OC1 cells, NO also showed substantial protection against H2O2-induced oxidative stress and cytotoxicity. Mechanistically, NO increased S-nitrosylation of pyruvate kinase M2 (PKM2) and inhibited its activity, which thus diverted glucose metabolic flux from glycolysis into the pentose phosphate pathway to increase production of reducing equivalents (NADPH and GSH) and eventually prevented H2O2-induced oxidative damage. These findings open new avenues for protection of cochlear hair cells from oxidative stress and prevention of NIHL through NO modulation of PKM2 and glucose metabolism reprogramming.

Enzymatic and Chemical Syntheses of Vacor Analogs of Nicotinamide Riboside, NMN and NAD.

It has recently been demonstrated that the rat poison vacor interferes with mammalian NAD metabolism, because it acts as a nicotinamide analog and is converted by enzymes of the NAD salvage pathway. Thereby, vacor is transformed into the NAD analog vacor adenine dinucleotide (VAD), a molecule that causes cell toxicity. Therefore, vacor may potentially be exploited to kill cancer cells. In this study, we have developed efficient enzymatic and chemical procedures to produce vacor analogs of NAD and nicotinamide riboside (NR). VAD was readily generated by a base-exchange reaction, replacing the nicotinamide moiety of NAD by vacor, catalyzed by Aplysia californica ADP ribosyl cyclase. Additionally, we present the chemical synthesis of the nucleoside version of vacor, vacor riboside (VR). Similar to the physiological NAD precursor, NR, VR was converted to the corresponding mononucleotide (VMN) by nicotinamide riboside kinases (NRKs). This conversion is quantitative and very efficient. Consequently, phosphorylation of VR by NRKs represents a valuable alternative to produce the vacor analog of NMN, compared to its generation from vacor by nicotinamide phosphoribosyltransferase (NamPT).

Automated Prediction of Cardiorespiratory Deterioration in Patients With Single Ventricle

BackgroundPatients with single-ventricle physiology have a significant risk of cardiorespiratory deterioration between their first and second stage palliation surgeries. ObjectivesThe objective of this study is to develop and validate a real-time computer algorithm that can automatically recognize physiological precursors of cardiorespiratory deterioration in children with single-ventricle physiology during their interstage hospitalization. MethodsA retrospective study was conducted from prospectively collected physiological data of subjects with single-ventricle physiology. Deterioration events were defined as a cardiac arrest requiring cardiopulmonary resuscitation or an unplanned intubation. Physiological metrics were derived from the electrocardiogram (heart rate, heart rate variability, ST-segment elevation, and ST-segment variability) and the photoplethysmogram (peripheral oxygen saturation and pleth variability index). A logistic regression model was trained to separate the physiological dynamics of the pre-deterioration phase from all other data generated by study subjects. Data were split 50/50 into model training and validation sets to enable independent model validation. ResultsOur cohort consisted of 238 subjects admitted to the cardiac intensive care unit and stepdown units of Texas Children’s Hospital over a period of 6 years. Approximately 300,000 h of high-resolution physiological waveform and vital sign data were collected using the Sickbay software platform (Medical Informatics Corp., Houston, Texas). A total of 112 cardiorespiratory deterioration events were observed. Seventy-two of the subjects experienced at least 1 deterioration event. The risk index metric generated by our optimized algorithm was found to be both sensitive and specific for detecting impending events 1 to 2 h in advance of overt extremis (receiver-operating characteristic curve area: 0.958; 95% confidence interval: 0.950 to 0.965). ConclusionsOur algorithm can provide 1 to 2 h of advanced warning for 62% of all cardiorespiratory deterioration events in children with single-ventricle physiology during their interstage period, with only 1 alarm being generated at the bedside per patient per day.

Nicotinamide Protects Against Diet-Induced Body Weight Gain, Increases Energy Expenditure, and Induces White Adipose Tissue Beiging.

Interventions that boost NAD+ availability are of potential therapeutic interest for obesity treatment. The potential of nicotinamide (NAM), the amide form of vitamin B3 and a physiological precursor of nicotinamide adenine dinucleotide (NAD)+ , in preventing weight gain has not previously been studied in vivo. Other NAD+ precursors have been shown to decrease weight gain; however, their impact on adipose tissue is not addressed. Two doses of NAM (high dose: 1% and low dose: 0.25%) are given by drinking water to C57BL/6J male mice, starting at the same time as the high-fat diet feeding. NAM supplementation protects against diet-induced obesity by augmenting global body energy expenditure in C57BL/6J male mice. The manipulation markedly alters adipose morphology and metabolism, particularly in inguinal (i) white adipose tissue (iWAT). An increased number of brown and beige adipocyte clusters, protein abundance of uncoupling protein 1 (UCP1), mitochondrial activity, adipose NAD+ , and phosphorylated AMP-activated protein kinase (P-AMPK) levels are observed in the iWAT of treated mice. Notably, a significant improvement in hepatic steatosis, inflammation, and glucose tolerance is also observed in NAM high-dose treated mice. NAM influences whole-body energy expenditure by driving changes in the adipose phenotype. Thus, NAM is an attractive potential treatment for preventing obesity and associated complications.

Modulating the quantity of HIV Env-specific CD4 T cell help promotes rare B cell responses in germinal centers.

Immunodominance to nonneutralizing epitopes is a roadblock in designing vaccines against several diseases of high interest. One hypothetical possibility is that limited CD4 T cell help to B cells in a normal germinal center (GC) response results in selective recruitment of abundant, immunodominant B cells. This is a central issue in HIV envelope glycoprotein (Env) vaccine designs, because precursors to broadly neutralizing epitopes are rare. Here, we sought to elucidate whether modulating the quantity of T cell help can influence recruitment and competition of broadly neutralizing antibody precursor B cells at a physiological precursor frequency in response to Env trimer immunization. To do so, two new Env-specific CD4 transgenic (Tg) T cell receptor (TCR) mouse lines were generated, carrying TCR pairs derived from Env-protein immunization. Our results suggest that CD4 T cell help quantitatively regulates early recruitment of rare B cells to GCs.

Calcilytic NPS 2143 Reduces Amyloid Secretion and Increases sAβPPα Release from PSEN1 Mutant iPSC-Derived Neurons.

Despite numerous efforts and studies over the last three decades, Alzheimer’s disease (AD) remains a disorder not fully understood and incurable so far. Development of induced pluripotent stem cell (iPSC) technology to obtain terminally differentiated neurons from adult somatic cells revolutionized the study of AD, providing a powerful tool for modelling the disease and for screening candidate drugs. Indeed, iPSC reprogramming allowed generation of neurons from both sporadic and familial AD patients with the promise to recapitulate the early pathological mechanisms in vitro and to identify novel targets. Interestingly, NPS 2143, a negative allosteric modulator of the calcium sensing receptor, has been indicated as a possible therapeutic for AD. In the present study, we assessed the potential of our iPSC-based familial AD cellular model as a platform for drug testing. We found that iPSC-derived neurons respond to treatment with γ-secretase inhibitor, modifying the physiological amyloid-β protein precursor (AβPP) processing and amyloid-β (Aβ) secretion. Moreover, we demonstrated the expression of calcium sensing receptor (CaSR) protein in human neurons derived from healthy and familial AD subjects. Finally, we showed that calcilytic NPS 2143 induced a changing of Aβ and sAβPPα secreted into conditioned media and modulation of CaSR and PSEN1 expression at the plasma membrane of AD neurons. Overall, our findings suggest that NPS 2143 affects important AD processes in a relevant in vitro system of familial AD.

Teaching physics for tomorrow: Equipping students to change the world

Why should engineers have all the fun?

PO-248 The role of ER stress in arginine deprivation-induced radiosensitization and cell death of HNSCC cells

IntroductionPancreatic ductal adenocarcinoma (pdac) is one of the most lethal human cancers. about 20–30% of pdac are described to be auxotrophic for arginine and thus might be particularly sensitive to arginine deprivation therapy (adt). although radiotherapy for treatment of pdca is controversially discussed, the abnormal metabolism of pdac in combination with radiation is an attractive approach for targeted therapy. previously, we could show that adt is efficient in radiosensitizing auxotrophic pdacs to photons. recent clinical studies imply a benefit of proton radiotherapy for pdac patients. we therefore systematically compared the sensitivity of pdac cells to photon and proton irradiation in combination with adt as well as gemcitabine treatment.Material and methodsHuman and murine auxotrophic pdacs cells mimicking a patient cohort were studied. adt was achieved with 2 u/ml of recombinant human arginase +/- citrulline, a physiological precursor of arginine. single doses ≤ 30 gy of 200 kv x-rays or 150 mev double-scattered protons were applied. treatment response was assessed by 2-d clonogenic survival and/or 3-d spheroid control probability (scp) assays.results and discussionsadt led to a sensitization of pdac cells to x-rays in 2-d and 3-d culture. proton irradiation significantly reduced the scp and spheroid control dose 50% (scd50) relative to x-rays in the 3-d assay as reflected by a relative biological effectiveness (rbe) of 2.0. combining protons with adt further increased the rbe to 2.4. gemcitabine treatment did not improve radiotherapy outcome. however, the triple combination of adt, gemcitabine and proton irradiation had a highly synergistic effect (rbe = 3.0). extended mechanistic studies are ongoing.ConclusionFor pdac, adt in combination with gemcitabine and proton irradiation seems to be a very promising treatment strategy and should be further explored for translation into clinical trials.

PO-247 Beneficial therapeutic ménage à trois: enzymotherapeutic arginine-deprivation, gemcitabine and proton irradiation for pancreatic cancer treatment - a systematic in vitro study

IntroductionPancreatic ductal adenocarcinoma (pdac) is one of the most lethal human cancers. about 20–30% of pdac are described to be auxotrophic for arginine and thus might be particularly sensitive to arginine deprivation therapy (adt). although radiotherapy for treatment of pdca is controversially discussed, the abnormal metabolism of pdac in combination with radiation is an attractive approach for targeted therapy. previously, we could show that adt is efficient in radiosensitizing auxotrophic pdacs to photons. recent clinical studies imply a benefit of proton radiotherapy for pdac patients. we therefore systematically compared the sensitivity of pdac cells to photon and proton irradiation in combination with adt as well as gemcitabine treatment.Material and methodsHuman and murine auxotrophic pdacs cells mimicking a patient cohort were studied. adt was achieved with 2 u/ml of recombinant human arginase +/- citrulline, a physiological precursor of arginine. single doses ≤ 30 gy of 200 kv x-rays or 150 mev double-scattered protons were applied. treatment response was assessed by 2-d clonogenic survival and/or 3-d spheroid control probability (scp) assays.results and discussionsadt led to a sensitization of pdac cells to x-rays in 2-d and 3-d culture. proton irradiation significantly reduced the scp and spheroid control dose 50% (scd50) relative to x-rays in the 3-d assay as reflected by a relative biological effectiveness (rbe) of 2.0. combining protons with adt further increased the rbe to 2.4. gemcitabine treatment did not improve radiotherapy outcome. however, the triple combination of adt, gemcitabine and proton irradiation had a highly synergistic effect (rbe = 3.0). extended mechanistic studies are ongoing.ConclusionFor pdac, adt in combination with gemcitabine and proton irradiation seems to be a very promising treatment strategy and should be further explored for translation into clinical trials.

Objectively Measured Sedentary Behavior, Physical Activity, and Cardiometabolic Risk in Hispanic Youth: Hispanic Community Health Study/Study of Latino Youth.

Time spent in moderate-to-vigorous physical activity (MVPA), but not in sedentary behavior (SB), is related to cardiometabolic risk among non-Hispanic white youth. Examine associations of SB and MVPA with cardiometabolic risk factors among Hispanic/Latino youth. Cross-sectional analysis. Four US communities. Hispanic/Latino youth (N = 1,426) ages 8 to 16 years. Associations of MVPA and SB, measured using 7-day accelerometer data (independent variables), with markers of glucose and lipid metabolism, inflammation, and endothelial function (dependent variables), were assessed in multivariable linear regression models while adjusting for sociodemographic characteristics and accelerometer wear time. Additional models controlled for obesity measures. SB comprised a mean (SD) of 75% (13%) of accelerometer wear time; mean (SD) time of MVPA was 35 min/d (22 min/d). Deleterious levels of high-density lipoprotein-cholesterol (HDL-C), triglycerides, insulin resistance, C-reactive protein, and plasminogen activator inhibitor-1 were associated with lower levels of MVPA and higher levels of SB (all P < 0.05). Associations of MVPA with log-transformed triglyceride concentrations (β per 15-min/d increment, -0.039; SE, 0.018; P = 0.037) and SB with HDL-C (β per 30-min/d increment, -0.63; SE, 0.26; P = 0.018), but not those with other markers, remained significant after adjusting for MVPA or SB and further adjustment for body mass index and waist circumference. Higher SB tertiles were associated with lower soluble receptor for advanced glycation end products in fully adjusted models (P for trend = 0.037). Physiological precursors of diabetes and cardiovascular disease were associated with MVPA and SB among US Hispanic/Latino youth, a group that bears a disproportionate burden of metabolic disorders.

Nicotinamide Improves Aspects of Healthspan, but Not Lifespan, in Mice

The role in longevity and healthspan of nicotinamide (NAM), the physiological precursor of NAD+, is elusive. Here, we report that chronic NAM supplementation improves healthspan measures in mice without extending lifespan. Untargeted metabolite profiling of the liver and metabolic flux analysis of liver-derived cells revealed NAM-mediated improvement in glucose homeostasis in mice on a high-fat diet (HFD) that was associated with reduced hepatic steatosis and inflammation concomitant with increased glycogen deposition and flux through the pentose phosphate and glycolytic pathways. Targeted NAD metabolome analysis in liver revealed depressed expression of NAM salvage in NAM-treated mice, an effect counteracted by higher expression of de novo NAD biosynthetic enzymes. Although neither hepatic NAD+ nor NADP+ was boosted by NAM, acetylation of some SIRT1 targets was enhanced by NAM supplementation in a diet- and NAM dose-dependent manner. Collectively, our results show health improvement in NAM-supplemented HFD-fed mice in the absence of survival effects.

Effect of Integrated Use of L-Tryptophan and Chemical Fertilizer on Growth and Yield Performances of Radish (&lt;em&gt;Rhaphanus sativus&lt;/em&gt; L.)

L-Tryptophan (L-TRP) is an essential amino acid that performs as a physiological precursor of auxins in higher plants. A pot experiment was conducted at the Agro Technology Park, Eastern University of Sri Lanka to find out the effect of integrated use of L-Tryptophan (L-TRP) and chemical fertilizer on growth and yield performance of Rhaphanus sativus L. There were six treatments with three replicates laid out in a Completely Randomized Design in a factorial arrangement. The treatment combinations were rates of fertilizer (recommended fertilizer rate by the Department of Agriculture and half of that recommendation), and concentration of L-TRP (0 M, 10-3 M, 10-4 M). Measurements were taken at 45 days after sowing of radish. There was a significant interaction (p<0.05) between the concentration of L-TRP and fertilizer rate on tested parameters of radish. All the tested parameter were significantly increased at 10-4 M of L-TRP over the control at recommended fertilizer rate while at half of recommended fertilizer rate, all the parameters were significantly high at 10-3 M of L-TRP over the control. It can be concluded that the application of L-TRP as a phytohormone precursor can be used to increase the growth and yield performance in radish at different fertilizer rate.