Transcription-related metabolic regulation in grafted lemon seedlings under magnesium deficiency stress.

Magnesium is one of the essential nutrients for plant growth, and plays a pivotal role in plant development and metabolism. Soil magnesium deficiency is evident in citrus production, which ultimately leads to failure of normal plant growth and development, as well as decreased productivity. Citrus is mainly propagated by grafting, so it is necessary to fully understand the different regulatory mechanisms of rootstock and scion response to magnesium deficiency. Here, we characterized the differences in morphological alterations, physiological metabolism and differential gene expression between trifoliate orange rootstocks and lemon scions under normal and magnesium-deficient conditions, revealing the different responses of rootstocks and scions to magnesium deficiency. The transcriptomic data showed that differentially expressed genes were enriched in 14 and 4 metabolic pathways in leaves and roots, respectively, after magnesium deficiency treatment. And the magnesium transport-related genes MHX and MRS2 may respond to magnesium deficiency stress. In addition, magnesium deficiency may affect plant growth by affecting POD, SOD, and CAT enzyme activity, as well as altering the levels of hormones such as IAA, ABA, GA3, JA, and SA, and the expression of related responsive genes. In conclusion, our research suggests that the leaves of lemon grafted onto trifoliate orange were more significantly affected than the roots under magnesium-deficient conditions, further indicating that the metabolic imbalance of scion lemon leaves was more severe.

[Relationship between peroxisome proliferator-activated receptor alpha intron 1A/C genetic polymorphism and metabolic syndrome].

OBJECTIVE: To identify the relationship between genetic polymorphisms of peroxisome proliferator-activated receptor alpha (PPARalpha) intron 1A/C and metabolic syndrome (MS) in a Chinese population. METHODS: A population-based case-control study was conducted in Suzhou city, Changshu County and Ganyu County in Jiangsu Province China, on the basis of an ongoing cohort study and 2348 cases were investigated. After the exclusion of the known MS cases, 1847 eligible subjects were successfully followed-up and their waist circumference (WC), body mass index, blood pressure, total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), triglycerides (TG) and fasting plasma glucose were measured. Newly diagnosed MS patients were recruited as cases, controls were individual matched with each case. TaqMan fluorescence probe method was used to detect the genetic polymorphism of PPARalpha intron 1A/C. RESULTS: The current analysis consisted of 389 MS patients and 389 matched controls. The C allele gene frequency of PPARalpha intron 1A/C in the case group was 22.24% (173/778), lower than that in the control group, which was 24.68% (192/778); whereas the difference was not statistically significant (chi(2) = 1.29, P > 0.05). In the genotypes AA + AC and CC, MS patients were accounted for 50.70% (363/716) and 41.94% (26/62) and hyperglycemia accounted for 21.37% (153/716) and 11.29% (7/62). Compared to the genotypes AA + AC, genotype CC was observed to be inversely associated with hyperglycemia (the adjusted OR = 0.39; 95%CI: 0.17 - 0.90) but not related to the occurrence of MS (OR = 0.75; 95%CI: 0.44 - 1.28) and other components of MS e.g., abdominal obesity (the adjusted OR = 0.67; 95%CI: 0.38 - 1.17), hypertriglyceridemia (the adjusted OR = 0.97; 95%CI: 0.53 - 1.76), low HDL-C (the adjusted OR = 0.72; 95%CI: 0.41 - 1.25) and hypertension (the adjusted OR = 0.72; 95%CI: 0.42 - 1.25) all P values > 0.05. CONCLUSION: C allele of PPARalpha intron 1A/C is not found to be associated with MS in the Chinese population. But comparing with the genotypes AA + AC, there is an inverse association between CC genotype and hyperglycemia.

[A nested case-control study on the relationship between occupational physical activity, heredity factors and metabolic syndrome].

OBJECTIVE: To examine the associations between occupational physical activity, heredity factors and metabolic syndrome (MS) in a Chinese population. METHODS: Based on the MS cohort study in Jiangsu province, subjects were followed-up, and blood samples were collected at the same time for biochemical indicators measurement. Newly confirmed MS patients according to US. National Cholesterol Education Program Adult Treatment Guidelines III (NCEP-ATPIII) were recruited as cases. Controls were 1:1 matched with cases by region, gender and age (+/- 2 years). In total, 389 MS patients and 389 controls were recruited as study subjects. Nested case-control study was applied for the present analysis. TaqMan fluorescence probe method was used to detect the genetic polymorphism of PPARalpha intron 1A/C(rs135539). RESULTS: (1) Compared to low physical activity group, the subjects with heavy physical activity were positively associated with MS (OR = 2.18, 95%CI: 1.08 - 4.38). (2) The subjects, with a family history of hypertension (OR = 1.44, 95%CI: 1.02 - 2.03) or type 2 diabetes (OR = 3.25, 95CI: 1.28 - 8.20), were significantly increased the occurrence of MS. (3) The genotype (AA, AC, CC) of PPARalpha intron 1A/C was not found to be related to MS. The OR of AC and CC genotype (compared to the genotype AA) were 0.98 (95%CI: 0.70 - 1.36) and 0.75 (95%CI: 0.44 - 1.29), respectively. (4) Effect modifications were observed between family history of hypertension and moderate physical activity (OR = 2.47, 95%CI: 1.00 - 6.06) or heavy physical activity (OR = 3.82, 95%CI: 1.31 - 11.15) on the development of MS. CONCLUSION: Heavy physical activity, with family history of hypertension or type 2 diabetes, seemed to be positively correlated with the risk of MS. Effect modifications were observed between occupational physical activity and family history of hypertension which might be associated with an increased risk of MS.