Polyamines (PAs) are positively charged amines that are present in all organisms. In addition to their functions specific to growth and development, they are involved in responding to various biotic and abiotic stress tolerance functions. The appropriate concentration of PA in the cell is maintained by a delicate balance between the catabolism and anabolism of PAs, which is primarily driven by two enzymes, namely diamine oxidase and polyamine oxidase (PAO). PAOs have been found to be localized in multiple subcellular locations, including peroxisomes. This paper presents a holistic account of peroxisomal PAOs. PAOs are flavin adenine dinucleotide-dependent enzymes with varying degrees of substrate specificity. They are expressed differentially upon various abiotic stress conditions, namely heat, cold, salinity, and dehydration. It has also been observed that in a particular species, the various PAO isoforms are expressed differentially with a spatial and temporal distinction. PAOs are targeted to peroxisome via a peroxisomal targeting signal (PTS) type 1. We conducted an extensive bioinformatics analysis of PTS1s present in various peroxisomal PAOs and present a consensus peroxisome targeting signal present in PAOs. Furthermore, we also propose an evolutionary perspective of peroxisomal PAOs. PAOs localized in plant peroxisomes are of potential importance in abiotic stress tolerance since peroxisomes are one of the nodal centers of reactive oxygen species (ROS) homeostasis and an increase in ROS is a major indicator of the plant being in stress conditions; hence, in the future, PAO enzymes could be used as a key candidate for generating abiotic stress tolerant crops.

Background: Polymorphism in genes associated with Vitamin-D metabolism and its receptor molecule altogether modulates the level of active serum Vitamin-D level and as such serves as potent immune modulator. Impact of this polymorphism on outcome of HBV related liver disease is poorly understood till date. Aim: This study focus on analysing the VDR polymorphism (TaqI, ApaI, and BsmI) and its associated molecules GC-Globulin and CYP2R1 among HBV infected patients and its probable correlation with disease progression. Method: Three hundred forty HBV infected patients belonging to three distinct clinical groups, Acute Viral hepatitis (AVH, n=205), Chronic Hepatitis (CH, n=84) and hepatocellular carcinoma (HCC, n = 51) along with 102 healthy control were included in the study. VDR, GC and CYP2R1 polymorphism were genotyped by PCR-RFLP method followed by Sanger sequencing. Haplotype distribution was analysed using SHEsis software. Logistic regression analysis was performed to find the association between different genotype and VDR haplotype with progression of liver disease. Further, an SVM based prediction model has also been described in detection of different disease stage. Results and Conclusion: Apa-I CC genotype was more frequently observed among chronic HBV patients and HCC than the acute cases among North east Indian population (OR = 2.241, C.I = 0.504- 5.558. p= 0.001). The occurrence of bAt haplotype was also found to be significantly higher among Chronic (p=0.004) and HCC (p=0.001<0.05) cases in comparison to acute cases. Further, logistic regression analysis after adjusting covariates like age, gender, serum AST/ALT level, serum albumin and platelet count, showed that Apa-I CC genotype and bAt haplotype were independent predictors for advancement of acute to chronic HBV infection and further. The SVM based prediction model using similar covariates also predicts the different disease stage with 90% accuracy.