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Objective. MicroRNAs have been revealed to be involved in the development of atherosclerosis. The present study is aimed at exploring the potential of miR-99a-5p as a therapy for atherosclerosis. We suspected that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy via constraining mTOR, therefore, alleviating atherosclerosis. Methods. The cell viability in ox-LDL-induced THP-1 macrophages was assessed by CCK-8 assay. Bioinformatic analysis was used to predict the target genes of miR-99a-5p. The binding between miR-99a-5p and mTOR was confirmed by luciferase reporter assay. In vivo, a high-fat-diet-induced atherosclerosis model was established in apolipoprotein E knockout mice. Hematoxylin-eosin, oil red O, and Sirius red staining were performed for the determination of atherosclerotic lesions. MTOR and associated protein levels were detected by Western blot analysis. Results. miR-99a-5p inhibited NLRP3 inflammasome activation and promoted macrophage autophagy by targeting mTOR. Enforced miR-99a-5p significantly reduced the levels of inflammasome complex and inflammatory cytokines. Furthermore, miR-99a-5p overexpression inhibited the expression of mTOR, whereas mTOR overexpression reversed the trend of the above behaviors. In vivo, the specific overexpression of miR-99a-5p significantly reduced atherosclerotic lesions, accompanied by a significant downregulation of autophagy marker CD68 protein expression. Conclusion. We demonstrated for the first time that miR-99a-5p may be considered a therapy for atherosclerosis. The present study has revealed that miR-99a-5p might inhibit NLRP3 inflammasome activation and promote macrophage autophagy by targeting mTOR, therefore, alleviating atherosclerosis.

Background: One of the causes of mortality among young people in modern societies is coronary heart disease (CHD). Numerous studies have demonstrated the association of major adverse cardiac events (MACEs) with percutaneous coronary intervention (PCI) in patients with premature CHD, but the risk factors for MACEs after PCI are poorly understood. This study investigated the risk factors for premature CHD after PCI and compared the long-term prognosis of patients with premature CHD with or without MACEs after PCI. In this paper, homocysteine was proven to be an independent risk factor for patients with early CHD. Animal studies have further demonstrated that atorvastatin inhibits homocysteine-induced inflammation, and homocysteine has preventive and therapeutic effects on patients with early CHD.Methods: A total of 1408 patients who underwent PCI were enrolled and divided into a MACE group and a non-MACE group according to the recurrence of cardiovascular events. Basic information and follow-up data of the patients were recorded, and risk factors affecting prognosis were analysed. Western blotting and reverse transcription polymerase chain reaction (RT–PCR) were used to verify that atorvastatin can inhibit the expression of NF-κB, IL-1β, IL-6, and CRP inflammatory factors induced by homocysteine, inhibiting the occurrence and development of atherosclerosis.Results: Univariate Cox proportional risk models showed that homocysteine level is one of a risk factors for recurrent MACEs. Further multivariate Cox regression analysis also suggested homocysteine is one of an independent risk factors for MACEs. The ROC curve showed that Hcy was a strong factor for predicting the occurrence of MACEs in patients with premature CHD. Atorvastatin was found to inhibit the expression of NF-κB, IL-1β, IL-6, and CRP inflammatory factors induced by homocysteine and delay the occurrence and development of reactive oxygen species.Conclusions: Homocysteineis an independent risk factor for MACEs in patients with premature CHD after PCI. Atorvastatin can effectively antagonize the expression of NF-κB, IL-1β, IL-6, CRP and other inflammatory factors induced by homocysteine.

Background: One cause of mortality among young people in modern societies is coronary heart disease (CHD). Numerous studies have demonstrated an association between major adverse cardiac events (MACEs) and percutaneous coronary intervention (PCI) in patients with premature CHD, but the risk factors for MACEs after PCI are poorly understood. This study investigated the risk factors for premature CHD after PCI and compared the long-term prognosis of patients with premature CHD with or without MACEs after PCI. Homocysteine was found to be an independent risk factor for patients with early CHD. Previous animal studies have demonstrated that atorvastatin inhibits homocysteine-induced inflammation and that atorvastatin has preventive and therapeutic effects in patients with early CHD.Methods: A total of 1408 patients who underwent PCI were enrolled and divided into a MACE group and a non-MACE group according to the recurrence of cardiovascular events. Basic information and follow-up data of the patients were recorded, and risk factors affecting prognosis were analysed. Western blotting and reverse transcription polymerase chain reaction were used to identify that atorvastatin inhibited the expression of NF-κB, IL-1β, IL-6, and CRP inflammatory factors induced by homocysteine, thereby inhibiting the occurrence and development of atherosclerosis.Results: Univariate Cox proportional risk models showed that the homocysteine level is a risk factor for recurrent MACEs. Multivariate Cox regression analysis also suggested that homocysteine is an independent risk factor for MACEs. The receiver operating characteristic curve showed that Hcy was a strong factor for predicting the occurrence of MACEs in patients with premature CHD. Atorvastatin was found to inhibit the expression of NF-κB, IL-1β, IL-6, and CRP inflammatory factors induced by homocysteine and delay the occurrence of reactive oxygen species.Conclusions: Homocysteine is an independent risk factor for MACEs in patients with premature CHD after PCI. Atorvastatin can effectively antagonize the expression of NF-κB, IL-1β, IL-6, CRP and other inflammatory factors induced by homocysteine.

The role of uric acid (UA) in survival of patients with hypertrophic obstructive cardiomyopathy (HOCM) has not been fully evaluated. This study aimed to determine whether UA could be an independent risk factor of cardiac death in patients with HOCM.A total of 317 patients with HOCM, who were receiving conservative treatment in Fuwai Hospital from October 2009 to December 2014, all of them completed UA evaluations, were analyzed. Patients were divided into three groups according to the UA levels: Tertile 1 (≤ 318 μmol/L,During a median follow-up of 45 months, 29 cardiac deaths (9.1%) occurred, including 6 sudden cardiac deaths and 23 heart failure-related deaths. Cardiac death in Tertile 3 (UA concentration was found to be independently associated with cardiac death in HOCM patients receiving conservative treatment. Randomized trials of UA-lowering agents for HOCM patients are warranted.

The efficacy and safety of proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not been evaluated. This study aims to describe the real world effectiveness of PCSK-9 inhibitors combined with statins compared with statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease (ASCVD).This is a multi-center observational study, enrolled patients from 32 hospitals who underwent percutaneous coronary intervention (PCI) from January to June in 2019. There are 453 patients treated with PCSK-9 inhibitors combined with statins in PCSK-9 inhibitor group and 2,610 patients treated with statins-based lipid lowering therapies in statins-based group. The lipid control rate and incidence of major adverse cardiovascular events (MACE) over six months were compared between two groups. A propensity score-matched (PSM) analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for MACE.In a total of 3,063 patients, 89.91% of patients had received moderate or high-intensity statins-based therapy before PCI, but only 9.47% of patients had low-density lipoprotein cholesterol (LDL-C) levels below 1.4 mmol/L at baseline. In the PSM selected patients, LDL-C level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81% (In the real world, PCSK-9 inhibitors combined with statins could significantly reduce LDL-C levels among patients with very high risk of ASCVD in China. The long-term clinical benefits for patients received PCSK-9 inhibitor to reduce the risk of MACE is still unclear and requires further study.

Background The efficacy and safety of PCSK-9 inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China is unknown. Objective To describe the real world effectiveness of initiated with PCSK-9 inhibitors combined with statins compared with statins among patients with very high risk of ASCVD and underwent percutaneous coronary intervention (PCI). Methods This is a prospective study, enrolled patients from 32 hospitals between January to June 2019. The lipid control rate and incidence of cardiovascular events over 6 months were compared between two groups. A propensity score-matched analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for cardiovascular events. Results In a total of 3063 patients, 89.91% had received moderate or high-intensity statin therapy before PCI, but only 9.47% had LDL levels below 1.4mmol/L at baseline. In the PSM selected patients, LDL level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81% (P

Objective To investigate the role of c-Jun NH2-terminal kinase (c-JNK) signaling pathway on voltage-gated potassium channel (Kv) remodeling in left ventricular myocytes of diabetic rats, and explore the intrinsic regulatory mechanism. Methods Forty-five SD rats were randomly divided into DM group (n=25, modeling with streptozotocin induction) and control group (n=20, fed with normal diet). Transient outward potassium current (Ito) of rats' ventricular myocytes in DM group and control group was recorded by whole-cell patch-clamp method. The c-Jun activity was detected using a non-radioactive JNK kinase assay kit (Cell Signaling Technology). JNK inhibitor SP600125 was used to incubate the cardiomyocytes of diabetes rats in vitro, and then the changes of Ito in cardiomyocytes were observed. Thioredoxin reductase (TrxR) inhibitor--auranofin (AF) was used to treat the rats' cardiomyocytes incubated with SP600125, and then the changes of Ito in cardiomyocytes were observed. The content of Kv4.2 was tested using anti-Kv4.2 antibody, and the results were analyzed using a UVP bioimaging system. Results The JNK activity in DM group rose more than 1 times compared with control group, while the density of Ito decreased significantly (Control: 30.2±3.3pA/pF, n=16; DM: 15.3±2.1pA/pF, n=17; P

Flixweed (Descurainia Sophia L.) is a problematic weed in winter wheat fields in China, which causes great loss of wheat yield. A total of 46 flixweed accessions from winter wheat-planting areas were collected and used for the survey of resistance to tribenuron-methyl and Pro197 mutation diversity. According to the “R” resistance rating system, 16 flixweed accessions have evolved resistance to tribenuron-methyl, 13 accessions have high risk of developing resistance to this herbicide and 17 accessions are susceptible. The mutation of Pro197 codon (CCT) changed proline (Pro) into leucine (Leu) (homozygous, RR), serine (Ser, RR), histidine (His, RR), threonine (Thr, RR), Pro/Leu (heterozygous, RS), Pro/Ser (RS), Pro/His, Pro/Thr (RS) and Pro/Tyr (RS). Among these amino acid changes, a Pro197-Pro/Tyr (heterozygous, RS) substitution caused by the mutation of two successive nucleotides was identified for the first time in resistant weed species. In addition, the Pro197-His and Pro197-Pro/His mutations have not been reported previously in flixweed. Finally, a CPAS marker was developed to identify flixweed plants with or without Pro197 mutation.

Oxidative stress plays a major role in the pathogenesis of heart failure, where the contractile response to β-adrenergic stimulation is profoundly depressed. This condition involves L-type Ca2+channels, but the mechanisms underlying their impaired adrenergic regulation are unclear. Thus the present study explored the basis for impaired adrenergic control of Ca2+channels in a rat infarction model of heart failure. Patch-clamp recordings of L-type Ca2+current ( ICa,L) from ventricular myocytes isolated from infarcted hearts showed a blunted response to intracellular cAMP that was reversed by treatment with exogenous pyruvate. Biochemical studies showed that basal and cAMP-stimulated protein kinase A activities were similar in infarcted and sham-operated hearts, whereas molecular analysis also found that binding of protein kinase A to the α1Csubunit of voltage-gated Ca2+channel isoform 1.2 was not different between groups. By contrast, protein phosphatase 2A (PP2A) activity and binding to α1Cwere significantly less in infarcted hearts. The PP2A inhibitor okadaic acid markedly increased ICa,Lin sham-operated myocytes, but this response was significantly less in myocytes from infarcted hearts. However, pyruvate normalized ICa,Lstimulation by okadaic acid, and this effect was blocked by inhibitors of thioredoxin reductase, implicating a functional role for the redox-active thioredoxin system. Our data suggest that blunted β-adrenergic stimulation of ICaLin failing hearts results from hyperphosphorylation of Ca2+channels secondary to oxidation-induced impairment of PP2A function. We propose that the redox state of Ca2+channels or PP2A is controlled by the thioredoxin system which plays a key role in Ca2+channel remodeling of the failing heart.

Two Descurainia Sophia populations, HB16 and HB08, were discovered in China and exhibit high resistance levels to tribenuron-methyl. Resistance ratio values of HB16 and HB08 were 153.47 and 651.20, respectively. The extractable acetohydroxy acid synthase (AHAS) activity was similar between resistant and susceptible populations. However, AHAS from HB16 and HB08 was less sensitive to inhibition of tribenuron-methyl comparing to susceptible population. The tribenuron-methyl I50 values for HB16 and HB08 were 46.25 and 54.07 greater than that for susceptible population respectively. Pro-197-Ser and Pro-197-Leu mutations were identified in AHAS extracted from HB16 and HB08 plants respectively. AHAS insensitivity of resistant D. Sophia caused by Pro197 mutation could be responsible for high resistance to tribenuron-methyl.

c-Jun NH2-terminal kinase (JNK) and p38 kinase are key regulators of cardiac hypertrophy and apoptosis during pathological stress, but their role in regulating ion channels in the diseased heart is unclear. Thus, we compared the kinase profile and electrophysiological phenotype of the rat ventricle 6–8 weeks after myocardial infarction (MI). Molecular analyses showed that JNK and p38 activities were markedly increased in post-MI hearts, while parallel voltage-clamp studies in ventricular myocytes revealed a characteristic downregulation of transient outward K+ current (Ito) density. When post-MI myocytes were treated with JNK or p38 inhibitors, Ito density increased to control levels. Upregulation of Ito was also elicited by insulin-like growth factor-1, which decreased JNK/p38 activity in post-MI hearts, and these changes were blocked by the thioredoxin (Trx) reductase inhibitor auranofin. Consistent with activation of JNK-p38 signaling, binding of apoptosis signal-regulating kinase-1 with Trx1 was also markedly decreased post-MI, and was reversed by insulin-like growth factor-1 in an auranofin-sensitive manner. We conclude that expression of ventricular K+ channels is redox regulated and that chronic impairment of the Trx system in the post-MI heart contributes to Ito remodeling through sustained activation of apoptosis signal-regulating kinase-1-JNK-p38 signaling. The cardiac Trx system may thus be a novel therapeutic target to reverse or prevent ventricular arrhythmias in the failing heart. Antioxid. Redox Signal. 14, 25–35.

The ubiquitous tripeptide glutathione (GSH) is an essential factor in many biological processes, thus its depletion has a major impact on cell function and survival. In this study, we examined regulation of GSH in cardiomyocytes under chronic oxidative stress elicited by myocardial infarction (MI). Cardiac dysfunction was induced in rats by coronary artery ligation, and experiments were conducted in myocytes isolated from non-infarcted left ventricle and septum after 6-8 weeks. Fluorescence microscopy studies using the probe monochlorobimane showed that [GSH] in myocytes from post-MI hearts was 42% less than in sham control hearts (P < 0.05). However, depleted GSH levels were normalized after 5-6 h by an insulin mimetic (bis-peroxovanadium-1,10-phenanthroline, bpV(phen); 10 micromol l(-1)) or by exogenous pyruvate (5 mmol l(-1)). The increase in [GSH] by bpV(phen) was partly inhibited by buthionine sulphoximine (BSO; 50 micromol l(-1)), a blocker of GSH synthesis, and by 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU; 100 micromol l(-1)), an inhibitor of glutathione disulphide reductase. By comparison, the effect of pyruvate was not altered by BSO but was completely blocked by BCNU. Studies using inhibitors of signalling cascades indicated that upregulation of [GSH] by bpV(phen) in myocytes from post-MI hearts was mediated by mitogen activated protein kinase/extracellular signal-regulated kinase kinase 1/2 and p38 mitogen-activated protein kinase but not by phosphatidylinositol 3-kinase. The effect of pyruvate was not altered by any kinase inhibitor tested. In cells loaded with the probe TEMPO-9-AC to monitor superoxide anion, baseline fluorescence was 2.3-fold greater in post-MI myocytes than in sham control myocytes (P < 0.05) and was markedly decreased by diphenyleneiodonium (30 micromol l(-1)), an inhibitor of NADPH oxidase, exogenous GSH (10 mmol l(-1)) or bpV(phen). In parallel studies, [GSH] in post-MI myocytes was also normalized by diphenyleneiodonium or exogenous GSH. These data show that GSH is differentially regulated by receptor tyrosine kinase-dependent and -independent agonists that maintain functional GSH levels necessary to neutralize excess generation of reactive oxygen species in the failing heart.

Oxidative stress contributes to the arrhythmogenic substrate created by myocardial ischemia-reperfusion partly through a shift in cell redox state, a key modulator of protein function. The activity of many oxidation-sensitive proteins is controlled by oxidoreductase systems that regulate the redox state of cysteine thiol groups, but the impact of these systems on ion channel function is not well defined. Thus, we examined the roles of the thioredoxin and glutaredoxin systems in controlling K(+) channels in the ventricle. An oxidative shift in redox state was elicited in isolated rat ventricular myocytes by brief exposure to diamide, a thiol-specific, membrane-permeable oxidant. Voltage-clamp studies showed that diamide decreased peak outward K(+) current (I(peak)) evoked by depolarizing test pulses by 41% (+60 mV; p

Flixweed (Descurainia sophia L.) is a troublesome weed in winter wheat fields in China. Two flixweed accessions, HB08 and HB16 with a Pro-197-Leu and Pro-197-Ser AHAS-mutation respectively, have evolved very high levels resistance to sulfonylurea (SU) herbicide, tribenuron-methyl. Cross resistance of HB08 and HB16 to AHAS herbicides of SU, imidazolinone (IMI), triazolopyrimidine (TP) and pyrimidinyl-thiobenozoate (PTB) families was investigated by dose-response experiments. In addition, the effects of AHAS herbicides on the activity of AHAS extracted from HB08 and HB16 plants were evaluated. HB16 exhibited cross resistance to SU herbicides halosulfuron-methyl and triasulfuron, TP herbicides flumetsulam and penoxsulam, but displayed more sensitivity to IMI herbicide imazethapyr. By contrast, HB08 only showed cross resistance to SU herbicides halosulfuron-methyl and triasulfuron. The in vitro sensitivity of AHAS to AHAS herbicides is consistent with the results of dose-response experiments and the estimated Pearson’s r values for HB08 and HB16 are 0.996 and 0.912 respectively. These indicated that altered AHAS sensitivity was responsible mainly for cross resistance patterns observed in the two resistant biotypes.

To study the effect of lysophosphatidylcholine (LPC) on T-type calcium channel currents (I(Ca.T)) in cardiomyocytes, and identify the mechanism by which LPC accumulation in intracellular and/or interstitial space may uptake tachycardia and various arrhythmias during cardiac ischemia.Neonatal rat cardiomyocytes from 1 to 3-day-old Wistar rats and hypertrophied ventricular myocytes from Wistar rats were prepared. Human cardiac T-type calcium channel α1 subunits, Ca(V3.1) and Ca(V3.2), were stably expressed in HEK293 cells. In this study, cardiomyocytes and heterologous expression of human Ca(V3.1) and Ca(V3.2) components were measureed by whole-cell patch clamp to study the up-regulation of I(Ca.T) by LPC.LPC markedly accelerated the spontaneous beating rates of neonatal rat cardiomyocytes from (42±8) beats/min in control to (64 ±8) beats/min after LPC application for 5 min at the physiological [Ca(2+)](i) concentration (pCa=7.2). In neonatal cardiomyocytes, I(Ca.T) was significantly increased by 10 μmol/L LPC by 21.5% when [Ca(2+)](i) was high (pCa=7). Intracellular Ca(2+)-dependent augmentation of I(Ca.T) by LPC was confirmed not only in neonatal cardiomyocytes but also in adult ventricular myocytes from the hypertrophied hearts. In this experiment, I(Ca.T) was significantly increased by 10 μmol/L LPC by 23.5% when [Ca(2+)](i) was high (pCa=7), although it was unchanged when [Ca(2+)](i) was low (pCa=11), control: (3.8±0.2) pA/pF, n=16; LPC: (3.7±0.4) pA/pF, n=10. LPC exerted no effect on the Ca(V3.1) T-type Ca(2+) channel current (I(Ca(V)3.1)) regardless of the [Ca(2+)](i) concentration at a pCa of 7 or at a pCa of 11. In contrast, LPC up-regulated the Ca(V3.2) T-type Ca(2+) channel current (I(Ca(V)3.2)), which was much larger at a pCa of 7 [LPC=10 μmol/L: (68.8±2.1) pA/pF, n=10; LPC=50 μmol/L: (78.4±4.8) pA/pF, n=9)] than that at a pCa of 11 [(38.5±2.1) pA/pF, n=11].The present study indicates that LPC up-regulates the cardiac I(Ca.T) in physiological or higher [Ca(2+)](i) concentration, which may accelerate the pathophysiological cardiac automaticity and trigger tachyarrhythmias as novel ischemia-related mechanism.

γ-Glutamyl transpeptidase (γ-GT) is a key enzyme in GSH metabolism that regulates intracellular GSH levels in response to extracellular GSH (GSHo). The objective of this study was to identify the role of γ-GT in reversing pathogenic K+ channel remodeling in the diseased heart. Chronic ventricular dysfunction was induced in rats by myocardial infarction (MI), and studies were done after 6–8 wk. Biochemical assays of tissue extracts from post-MI hearts revealed significant increases in γ-GT activity in left ventricle (47%) and septum (28%) compared with sham hearts, which paralleled increases in protein abundance and mRNA. Voltage-clamp studies of isolated left ventricular myocytes from post-MI hearts showed that downregulation of transient outward K+ current ( Ito) was reversed after 4–5 h by 10 mmol/l GSHo or N-acetylcysteine (NACo), and that the effect of GSHo but not NACo was blocked by the γ-GT inhibitors, acivicin or S-hexyl-GSH. Inhibition of γ-glutamylcysteine synthetase by buthionine sulfoximine did not prevent upregulation of Ito by GSHo, suggesting that intracellular synthesis of GSH was not directly involved. However, pretreatment of post-MI myocytes with an SOD mimetic [manganese (III) tetrapyridylporphyrin] and catalase completely blocked recovery of Ito by GSHo. Confocal microscopy using the fluorogenic dye 2′,7′-dichlorodihydrofluorescein diacetate confirmed that GSHo increased reactive oxygen species (ROS) generation by post-MI myocytes and to a lesser extent in myocytes from sham hearts. Furthermore, GSHo-mediated upregulation of Ito was blocked by inhibitors of tyrosine kinase (genistein, lavendustin A, and AG1024) and thioredoxin reductase (auranofin and 13- cis-retinoic acid). These data suggest that GSHo elicits γ-GT- and ROS-dependent transactivation of tyrosine kinase signaling that upregulates K+ channel activity or expression via redox-mediated mechanisms. The signaling events stimulated by γ-GT catalysis of GSHo may be a therapeutic target to reverse pathogenic electrical remodeling of the failing heart.

In this paper proposes a new wavelet watermark technique based on the linear bit expansion. To ensure the security of the watermark, enlarged watermark by applying linear bit expansion is inserted in a given intensity to a low frequency sub-band of the image which is wavelet transformed after the Arnold Transformation. Using F norm function to detect the presence of watermark is applied which is different from existing methods. The experimental results verify that the proposed watermarking technique has outstanding quality in regards to fidelity and robustness.

The acetyl-CoA carboxylase (ACCase)-inhibiting cyclohexanedione herbicide clethodim is used to control grass weeds infesting dicot crops. In Australia clethodim is widely used to control the weed Lolium rigidum. However, clethodim resistant Lolium populations have appeared over the last five years and now are present in many populations across the Western Australian wheat belt (Owen et al. 2007). An Asp-2078-Gly mutation in the plastidic ACCase enzyme has been identified as the only known mutation endowing clethodim resistance (Délye et al. 2005). Here, with 14 clethodim resistant Lolium populations we revealed diversity and complexity in the molecular basis of resistance to ACCase-inhibiting herbicides (clethodim in particular). Several known ACCase mutations (Ile-1781-Leu, Trp-2027-Cys, Ile-2041-Asn and Asp-2078-Gly) and in particular, a new mutation of Cys to Arg at position 2088, were identified in plants surviving the Australian clethodim field rate (60 g ha-1). Twelve combination patterns of mutant alleles were revealed in relation to clethodim resistance. Through a molecular, biochemical and biological approach, we established that the mutation 2078-Gly or 2088-Arg endows sufficient level of resistance to clethodim at the field rate, and in addition, combinations of two mutant 1781-Leu alleles, or two different mutant alleles (i.e. 1781-Leu/2027-Cys, 1781-Leu/2041-Asn), also confer clethodim resistance. Plants homozygous for the mutant 1781, 2078 or 2088 alleles were found to be clethodim resistant and cross resistant to a number of other ACCase inhibitor herbicides including clodinafop, diclofop, fluazifop, haloxyfop, butroxydim, sethoxydim, tralkoxydim, and pinoxaden. We established that the specific mutation, the homo/heterozygous status of a plant for a specific mutation, and combinations of different resistant alleles plus herbicide rates all are important in contributing to the overall level of herbicide resistance in genetically diverse, cross-pollinated Lolium species.