Genome-wide analysis of CqCrRLK1Ls and CqRALFs in Chenopodium quinoa

Quinoa (Chenopodium quinoa) is a highly nutritious crop showing a remarkable tolerance to multiple abiotic stresses. The Catharanthus roseus RLK1-like kinase (CrRLK1L) family is involved in multiple processes during plant growth and stress responses. However, little is known about the members of the CqCrRLK1L subfamily and their biological functions. In this study, up to 26 CqCrRLK1L members were identified in quinoa genome. To systematically investigate their tissue-specific expression pattern and gene expression profiles in response to abiotic stresses, different quinoa samples including leaf, pistil, stamen, root, and leaf treated with NaCl were harvested for transcrioptome analysis with three biological replicates for each sample. Finally,we mapped about 30 million sequence reads per sample to the quinoa genome (NL-6) and combining the four different tissues (leaf, pistil, stamen, and root), totally 40382 genes were detected, accounting for 69% of total genes in quinoa. The expression of most CqCrRLK1Ls genes were detected in all four kind of tissues, and they showed tissue-specific expression pattern. In salt-treated leaves, we observe that about 6-thosands genes changed their expression, with log2FoldChange < -1 or >1 and p value <0.05. And four CqCrRLK1L genes largely altered their transcript levels, implying that these genes are involved in the regulation of salt stress response in quinoa. The present study provides a base for future research on elucidating the varied biological functions of CqCrRLK1Ls and their contributions to stress responses. Overall design: mRNA profiles of quinoa samples, including stamens and pistills of newly open flowers, roots of 3 days seedlings, leaves of 14 days plants exposure to 400 mM NaCl for 8 hours and the untreated controls.