Genome-wide identification and expression analysis of NIN-like protein (NLP) genes: Exploring their potential roles in nitrate response in tea plant (Camellia sinensis).

NIN-like proteins (NLPs) are evolutionarily conserved transcription factors that are unique to plants and play a pivotal role in responses to nitrate uptake and assimilation. However, a comprehensive analysis of NLP members in tea plants is lacking. The present study performed a genome-wide analysis and identified 33 NLP gene family members of Camellia sinensis that were distributed unequally across 5 chromosomes. Subcellular localisation predictions revealed that all CsNLP proteins were localised in the nucleus. Conservative domain analysis revealed that all of these proteins contained conserved RWP-RK and PB1 domains. Phylogenetic analysis grouped the CsNLP gene family into four clusters. The promoter regions of CsNLPs harboured cis-acting elements associated with plant hormones and abiotic stress responses. Expression profile analysis demonstrated that CsNLP8 was significantly upregulated in roots under nitrate stress conditions. Subcellular localisation analysis found CsNLP8 localised to the nucleus. Dual-luciferase reporter assay demonstrated that CsNLP8 positively regulated the expression of a nitrate transporter gene (CsNRT2.2). These findings provide a comprehensive characterisation of NLP genes in Camellia sinensis and offer insights into the biological function of CsNLP8 in regulating the response to nitrate-induced stress.

Investigating noncovalent interactions of rutin-serum albumin by capillary electrophoresis-frontal analysis.

The application of capillary electrophoresis-frontal analysis (CE-FA) to study noncovalent interaction between rutin and serum albumin (bovine serum albumin, BSA and human serum albumin, HSA) in phosphate buffer solution (67 mM, pH 7.4) at 37 degrees C is presented. Using fixed HSA or BSA concentration and increasing rutin concentration, the number of primary binding sites per HSA or BSA molecules, and the affinity constants were obtained. Both affinity constants are in a comparable range suggesting the similarity of affinity properties of HSA and BSA towards rutin. The proposed CE-FA method is simple, rapid and cost-effective which may be useful in further high-throughput protein binding studies of multi-components in traditional herbal medicines for pharmacological effect evaluations.