Tetraploids Isatis indigotica are more responsive and adaptable to stresses than the diploid progenitor based on changes in expression patterns of a cold inducible Ii CPK1

Abstract

In plants, Ca2+ -dependent protein kinases (CDPKs) are characterized as important sensors of Ca 2+ flux in response to varieties of biotic and abiotic stress. A comprehensive survey of global gene expression performed by using an Arabidopsis thaliana whole genome Affymetrix gene chip revealed that CDPK tends to be significantly higher in tetraploid Isatis indigotica than in diploid ones. To investigate different CDPK expression in response to polyploidy, a full-length cDNA clone (IiCPK1) encoding CDPK was isolated from the traditional Chinese medicinal herb I. indigotica cDNA library. IiCPK1 contains some basic features of CDPKs: a catalytic kinase domain including an ATP-binding domain and four EFhand calcium-binding motifs. Real-time PCR analysis indicated the expression of IiCPK1 from two kinds of I. indigotica (tetraploid and diploid). They both were induced in response to cold stress, but tetraploids I. indigotica which has good fertility, exhibited an enhanced resistance and higher yield, and presented to be more responsive and adaptable. Our results suggest that IiCPK1 gene plays a role in adapting to the environmental stress.

Transcriptomic Analysis Reveals Differential Gene Expressions for Cell Growth and Functional Secondary Metabolites in Induced Autotetraploid of Chinese Woad (Isatis indigotica Fort.)

“…Five signal transduction genes (Calcium-dependent protein kinase and Receptor-like kinase) were identified. One hundred and thirteen unigenes were clustered into a GO term of “response to stimulus”, of which 63 (55.8%) unigenes were up-regulated and 63 unigenes were clustered into “response to stress” with 35 (55.6%) up-regulated, indicating that Isatis indigotica tetraploids were more responsive and adaptable to stresses than the diploid progenitor [ 42 ]. In addition, some unigenes related with “cell wall and cell wall organization or biogenesis”, “cell growth” and “cell cycle” were identified and most of them were up-regulated in 4 x plants ( Table 2 ).…”

“…The expression of CDPK which encoded plant receptor-like kinases (RLKs) was induced in response to various environmental in different plant species [ 62 ]. Isatis indigotica tetraploids were reported to be more responsive and adaptable to stresses than the diploid by the changes in expression patterns of a cold inducible CDPK1 [ 42 ]. In our study, the expression of CDPK s and RLK s tended to be higher in the tetraploid than in diploid ( Table 2 ), which possibly made the tetraploid more adaptable under stress by altering CDPK mRNA level.…”

Linkage Mapping and QTL Analysis of Agronomic Traits in Tetraploid Potato (Solanum tuberosum subsp. tuberosum)

“…Despite these challenges, it is worthwhile to map and model traits in a tetraploid context because information from diploid potatoes regarding important traits cannot account for these higher‐order allelic interactions. In addition, the condition of polyploidy can cause changes in both genome organization (Song et al, 1995; Luo et al, 2004) and gene expression (Lu et al, 2006; Pan et al, 2008) that would not be present at the diploid level. The results of our QTL mapping study demonstrate some of the complexities of tetraploid genetics.…”

IiWRKY34 positively regulates yield, lignan biosynthesis and stress tolerance in Isatis indigotica

“…An Arabidopsis thaliana whole genome Affymetrix gene chip (ATH1) 10 was used to survey the variation of gene expression between tetraploid and diploid I. indigotica , and results revealed a coordinated induction and suppression of 715 and 251 ploidy-responsive genes in tetraploid I. indigotica , involving in various developmental, signal transduction, transcriptional regulation and metabolic pathways 11 . Some of them, such as a stomatal developmental gene IiSDD1 12 , two signal transduction genes IiCPK1 13 and IiCPK2 14 , and a lignan biosynthetic pathway gene IiPAL 15 , have been characterized to explore their contribution to the favorable physiological consequences after polyploidization. More recently, transcriptomic analysis of diploid and tetraploid I. indigotica indicated that the differentially expressed genes (DEGs) were mainly involved in cell growth, cell wall organization, secondary metabolite biosynthesis, stress response and photosynthetic pathways 16 .…”