ScChi, Encoding an Acidic Class III Chitinase of Sugarcane, Confers Positive Responses to Biotic and Abiotic Stresses in Sugarcane

Abstract

Chitinases (EC 3.2.2.14), expressed during the plant-pathogen interaction, are associated with plant defense against pathogens. In the present study, a positive correlation between chitinase activity and sugarcane smut resistance was found. ScChi (GenBank accession no. KF664180), a Class III chitinase gene, encoded a 31.37 kDa polypeptide, was cloned and identified. Subcellular localization revealed ScChi targeting to the nucleus, cytoplasm and the plasma membrane. Real-time quantitative PCR (RT-qPCR) results showed that ScChi was highly expressed in leaf and stem epidermal tissues. The ScChi transcript was both higher and maintained longer in the resistance cultivar during challenge with Sporisorium scitamineum. The ScChi also showed an obvious induction of transcription after treatment with SA (salicylic acid), H2O2, MeJA (methyl jasmonate), ABA (abscisic acid), NaCl, CuCl2, PEG (polyethylene glycol) and low temperature (4 °C). The expression levels of ScChi and six immunity associated marker genes were upregulated by the transient overexpression of ScChi. Besides, histochemical assay of Nicotiana benthamiana leaves overexpressing pCAMBIA 1301-ScChi exhibited deep DAB (3,3′-diaminobenzidinesolution) staining color and high conductivity, indicating the high level of H2O2 accumulation. These results suggest a close relationship between the expression of ScChi and plant immunity. In conclusion, the positive responses of ScChi to the biotic and abiotic stimuli reveal that this gene is a stress-related gene of sugarcane.

Sugarcane calcineurin B-like (CBL) genes play important but versatile roles in regulation of responses to biotic and abiotic stresses

“…The three recombinant ScCBL-GFP vectors were transformed into competent Agrobacterium tumefaciens GV3101 cells. The Agrobacterium-mediated transient expression in N. benthamiana leaves was performed according to the method described by Su et al 39 . After infiltration for 48 h, the subcellular localization of the fusion protein were visualized by laser scanning confocal microscopy (Leica TCS SP5, Wetzlar, Germany).…”

“…After incubation, the cells were centrifuged and resuspended in MS liquid medium (containing 200 μM acetosyringone) at an OD 600 of 0.8. After infiltration into the N. benthamiana leaves, the plants were cultured at 24 °C for 24 h (16 h light/8 h darkness) 39 . RT-PCR was exploited to detect whether ScCBL genes have been overexpressed in N. benthamiana, with the RNA of treated leaves and ScCBL genes specific primers (gScCBL2-1, gScCBL3-1, and gScCBL4, Table S1), and the NtEF1-α was treated as control.…”

Chitinases As The Key To The Interaction Between Plants And Microorganisms

“…Chitynazy klasy II i VII zbudowane są z domeny katalitycznej, która wykazuje duże podobieństwo do domeny CatD z klasy IV. Natomiast należące do rodziny GH 18 chi-tynazy z klasy III i V posiadają domenę katalityczną bez domeny wiążącej chitynę oraz regionu zawiasowego [42,90]. Tak duża różnorodność budowy strukturalnej chitynaz roślinnych wynika głównie z ewolucyjnych zmian w świecie roślin.…”

Small RNA sequencing reveals a role for sugarcane miRNAs and their targets in response to Sporisorium scitamineum infection

“…This assay was nearly 100 times more sensitive than conventional PCR for detection of this pathogen [8]. Su et al also obtained three members of the β-1,3-glucanase gene family ( ScGluA1 , ScGluD1 and ScGluD 2) [9, 10], one catalase gene ( ScCAT1 ) [11] and ten chitinase family genes [12], which are associated with the pathogenicity of sugarcane smut. Wu et al [13] used Solexa high-throughput sequencing for differential gene expression profiling of sugarcane after infection with sugarcane smut and 2,015 differentially expressed sequence tags (ESTs) were screened, including three upregulated ESTs that were related to the mitogen-activated protein kinase (MAPK) signaling pathways.…”