Cloning of the Aegiceras corniculatum class I chitinase gene (AcCHI I) and the response of AcCHI I mRNA expression to cadmium stress

Abstract

Chitinases in terrestrial plants have been reported these are involved in heavy metal tolerance/detoxification. This is the first attempt to reveal chitinase gene (AcCHI I) and its function on metal detoxification in mangroves Aegiceras corniculatum. RT-PCR and RACE techniques were used to clone AcCHI I, while real-time quantitative PCR was employed to assess AcCHI I mRNA expressions in response to Cadmium (Cd). The deduced AcCHI I protein consists of 316 amino acids, including a signal peptide region, a chitin-binding domain (CBD) and a catalytic domain. Protein homology modeling was performed to identify potential features in AcCHI I. The CBD structure of AcCHI I might be critical for metal tolerance/homeostasis of the plant. Clear tissue-specific differences in AcCHI I expression were detected, with higher transcript levels detected in leaves. Results demonstrated that a short duration of Cd exposure (e.g., 3 days) promoted AcCHI I expression in roots. Upregulated expression was also detected in leaves under 10 mg/kg Cd concentration stress. The present study demonstrates that AcCHI I may play an important role in Cd tolerance/homeostasis in the plant. Further studies of the AcCHI I protein, gene overexpression, the promoter and upstream regulation will be necessary for clarifying the functions of AcCHI I.

Early transcriptional response pathways in Daphnia magna are coordinated in networks of crustacean‐specific genes

“…Interestingly, the glutathione S-transferases are upregulated under heavy metals but appear to be both up and down-regulated under osmotic stress ( Dapma7bEVm002921t1, Dapma7bEVm010893t1 ; Table S1). In addition to the well-known chitin remodelling response to heavy metals (Bekesiova et al 2008; Lanfranco et al 2004; Poynton et al 2007; Wang et al 2015), mediated by strong up-regulation of genes encoding chitinases, cuticle proteins, and cuticle binding proteins (Table S1), we see the activation and repression of numerous trypsins and trypsin inhibitors under heavy metals and UV treatments. These differentially expressed genes indicate regulation of digestive enzymes and associated processes, similarly to reported response in Drosophila melanogaster under heavy metal exposure (Brown et al 2014).…”

Identification of key genes and modules in response to Cadmium stress in different rice varieties and stem nodes by weighted gene co-expression network analysis

“…Dana et al reported overexpressing chitinases tobacco showed exhibit enhanced levels of resistance to biotic and abiotic stress 27 . In addition, Wang et al found the up-regulated AcCHI I mRNA in response to Cd stress 28 . All these findings further confirmed the important role of chitinases in against Cd stress.…”

Morphological Responses and Gene Expression of Grain Amaranth (Amaranthus spp.) Growing under Cd

“…These pathogenesis-related proteins are known to be involved in plant responses to various abiotic stress stimuli such as salinity, wounding, cold, and osmotic stress [52]. They have also been reported to be part of the metal stress defence [53][54][55][56][57].…”

“…A number of crops are significantly responsive to Cd stress via changes in chitinase gene expression and /or chitinase activity, e.g., Pisum sativum Vicia faba, Pisum sativum, Hordeum vulgare, Zea mays, Glycine max, Avicennia marina and Aegiceras corniculatum [52,[54][55][56][57][58][59]. Although the activities of individual chitinase genes are cultivar-and metal compound-dependent, they are apparently involved in the plant response against heavy metals and metal detoxification in plants [53].…”