Small RNA profiling of Cavendish banana roots inoculated with Fusarium oxysporum f. sp. cubense race 1 and tropical race 4

Abstract

Fusarium wilt, caused by the soil-borne fungal pathogen, Fusarium oxysporum f. sp. cubense (Foc), is considered as one of the most threatening diseases of banana. The Cavendish variety, resistant to Foc race 1 (R1), is susceptible to tropical race 4 (TR4), an aggressive race of the pathogen which is of increasing concern worldwide. Previous studies have revealed that plant small RNAs (sRNAs) play crucial roles in the host response to pathogen infection. To investigate the roles of sRNAs involved in the interaction of the banana-Foc pathosystem, small RNA profiles of Cavendish banana roots inoculated with Foc TR4 and Foc R1 were obtained and analyzed in the present study using Next-Generation Sequencing (NGS) technology. A total of 112 discrete mature microRNAs (miRNAs) belonging to 22 known miRNA families were found across all constructed sRNA libraries. The expression of miR166, miR159 and miR156 was upregulated in TR4-inoculated samples as compared to mock-inoculated samples, while the expression of these miRNAs was approximately the same in R1-inoculated and mock-inoculated samples. Consistent with the sequencing data, qRT-PCR results demonstrated up-regulation of these miRNAs and down-regulation of their target genes in TR4-inoculated samples, but not in R1-inoculated samples. Considering Cavendish banana is resistant to R1 and susceptible to TR4, it is possible that these sRNAs and their target genes are involved in particular plant defence pathways such as salicylic acid-based defence. The findings will pave way for future investigations of the defence mechanism and potential approaches of resistance improvement.

Characterization of microRNAs and Target Genes in Musa acuminata subsp. burmannicoides, var. Calcutta 4 during Interaction with Pseudocercospora musae

“…Although Musa miRNAs have been characterized in relation to responses to drought, salt, and temperature stresses [ 56 , 66 , 67 ], as well as in relation to evolutionary changes across different Musa subgroups [ 68 ], analyses in the context of biotic stress responses have been limited to cultivars contrasting in resistance to F. oxysporum f. sp. cubense races [ 40 , 57 , 58 ]. No investigation, prior to this study, has been conducted on miRNA characterization and expression analysis in the M. acuminata–P.…”

“…Ref. [ 58 ] also reported over 110 mature miRNAs during the interaction of Cavendish banana root tissue with F. oxysporum f. sp. cubense tropical race 4 and F. oxysporum f. sp.…”

Revealing disease‐specific endogenous target mimic of microRNA from long non‐coding RNA identification and characterization in Musa spp.

“…Furthermore, one of the lncRNA transcripts from both representatives were picked, TCONS_00057826 (Figure 6) was picked from klutuk banana, and it can be predicted from compu tational methods that it potentially has 45 interactions with miRNA. About 33% of the interactions showed the binding of lncRNA with the miR444 miRNA family, which hypothe sized to have a role in the stress response to Fusarium wilt by FocTR4 in banana plants and responses to low temper atures (Fei et al 2019). miR444 in rice plants can increase defence against RSV virus attacks by increasing the ex pression of the OsRDR1 (antiviral RNA silencing) gene (Wang et al 2016).…”

Exploring diverse roles of micro RNAs in banana: Current status and future prospective

“…How miRNA 169 plays a key role in resistance towards Foc in banana is still not clear but evidences from tomato plants resistant to graymold indicates targeting of NF‐YA5 transcription factor by miRNA 169 (Li, Li, Ju, et al, 2016; Li, Li, Zhou, et al, 2016; Song et al, 2018). A study on Cavendish banana which is resistant to Foc race1 species shows up‐regulation of mir156, mir159 and mir166 in the roots of infected plants (Fei et al, 2019). mir159 and mir166 are reported as negative regulator of abscisic acid signalling pathway and positive regulator of salicylic acid pathway suggesting a possibility of augmenting the salicylic acid mediated defence pathway by these miRNAs during the resistance mechanism of the host (De Torres‐Zabala et al, 2007; Zhang et al, 2011).…”