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This article is a Commentary on Shi et al. (2024), 242: 2541–2554. [ABSTRACT FROM AUTHOR]

MYB and bHLH are large transcription factor families with largely uncharacterized biological functions. The patterns of expression of 42 MYB and 58 bHLH transcription factor genes were examined in potato clones that were demonstrated to have variation in anthocyanin intensity and common scab resistance to assess their possible involvement in regulating these traits. The control of expression of biosynthetic enzymes in regulation of anthocyanin intensity was also evaluated. The dihydroflavonol 4-reductase (DFR) gene, a key enzyme in the pathway, had the highest correlation with gene expression and anthocyanin intensity (quantified as levels of anthocyanidins). Expression of five uncharacterized MYB and three bHLH genes was also highly correlated with anthocyanin intensity, suggesting that they could be regulators of biosynthetic enzyme gene expression. The same potato clones were also demonstrated to have variation in resistance to Streptomyces scabiei, the causal pathogen of common scab in potato. Correlation analysis was used to show that anthocyanin intensity was not associated with common scab resistance. However, common scab resistance was correlated with expression of another two MYB and three bHLH genes, indicating that they might be involved in the regulation of the defense response of potato against the common scab pathogen. Key words: anthocyanin, potato, common scab, MYB, bHLH, gene expression, anthocyanin biosynthetic enzymes. Resume: Les MYB et bHLH constituent des familles grands facteurs de transcription aux fonctions biologiques generalement non caracterisee. Les auteurs ont examine le patron d'expression du 42 genes MYB et 58 genes bHLH facteurs de transcription chez des clones de pomme de terre les patrons ayant demontre des variations dans l'intensite de l'anthocyanine et une resistance a la gale commune, afin d'evaluer leur implication possible dans la regulation de ces caracteres. Ils ont egalement evalue le controle de l'expression des enzymes de biosynthese dans la regulation de l'intensite de l'anthocyane. Le gene de la 4-reductase dihydroflavonol (DFR), une enzyme cle dans le sentier, montre la plus forte correlation avec l'expression du gene et l'intensite de l'anthocyane (quantifiee comme degres d'anthocyanidine). L'expression de cinq genes MYB et trois genes bHLH montre une fort correlation avec l'intensite de l'anthocyanine ce qui suggere qu'ils pourraient agir comme regulateurs de l'expression du gene de l'enzyme biosynthetique. On a egalement demontre que les memes clones de pomme de terre montrent une variation de resistance envers le Streptomyces scabiei, l'agent pathogene causal de la gale commune de la pomme de terre. Les auteurs ont utilise l'analyses des correlations pour montrer que l'intensite de l'anthocyane n'est pas correlee avec la resistance a la gale commune. Cependant, la resistance a la gale commune montre une correlation avec l'expression de deux autres genes MYB et trois autres genes bHLH indiquant qu'ils pourraient etre impliques dans la regulation de la reaction de defense de la pomme de terre contre l'agent pathogene de la gale commune. [Traduit par la Redaction] Mots-cles : anthocyane, pomme de terre, gale commune, MYB, bHLH, expression genetique, enzyme biosynthetique de l'anthocyane., Introduction Regulatory networks controlling plant morphology and physiology involve transcription factors that bind to promoters of target genes to increase or decrease gene expression in response to developmental and environmental [...]

Proteins from the seeds of 12 cultivars of three lupin species were analyzed by gel electrophoresis. Similarities between cultivars of the same species were noted. Antibodies raised against the three major globular proteins, conglutin [Alpha], [Beta], and [Gamma], of Lupinus albus cv. Ultra were used to probe immunoblots of crude extracts. The immunoblots revealed variations between cultivars not previously resolved and identified which protein subunits were derived from which conglutin. In vitro digestibility studies were done on four of the lupin cultivars. During the digestion of these cultivars, the large protein units were shown to be degraded to smaller intermediates with specific molecular sizes. Some of the intermediate protein subunits were identified as being derived from conglutin [Beta]. The digestibility of the four cultivars, based on the amount of identifiable protein in the ruminal fluid digest at 9 and 24 h, showed Ultra > Primorski > Juno > Danja. From this study a novel system of analyzing protein digestibility was devised. Key Words: Lupins, Electrophoresis, Immunoblotting, Digestibility, Protein

Potato (Solanum tuberosum L.) is an important staple crop with a highly heterozygous and complex genome. Despite its cultural and economic significance, potato improvement efforts have been held back by the relative lack of genetic resources available to producers and breeders. The publication of the potato reference genome and advances in high-throughput sequencing technologies have led to the development of a wide range of genomic and transcriptomic resources. An overview these new tools, from the updated versions of the potato reference genome and transcriptome, to more recent gene expression, regulatory motif, re-sequencing and SNP genotyping analyses, paints a picture of modern potato research and how it will change our understanding of potato as well as other tuber producing Solanaceae. [ABSTRACT FROM AUTHOR]

The potato is susceptible to water stress at all stages of development. We examined four clones of tetraploid potato, Cardinal, Desirée, Clone 37 FB, and Mije, from the germplasm bank of the National Institute of Agricultural Research (INIA) in Chile. Water stress was applied by suspending irrigation at the beginning of tuberization. Stomatal conductance, and tuber and plant fresh and dry weight were used to categorize water stress tolerance. Cardinal had a high susceptibility to water stress. Desirée was less susceptible than Cardinal and had some characteristics of tolerance. Mije had moderate tolerance and Clone 37 FB had high tolerance. Differential gene expression in leaves from plants with and without water stress were examined using transcriptome sequencing. Water stress-susceptible Cardinal had the fewest differentially expressed genes at 101, compared to Desirée at 1867, Clone 37 FB at 1179, and Mije at 1010. Water stress tolerance was associated with upregulation of the expression of transcription factor genes and genes involved in osmolyte and polyamine biosynthesis. Increased expression of genes encoding late embryogenesis abundant (LEA) and dehydrin proteins along with decreased expression of genes involved in nitrate assimilation and amino acid metabolism were found for clones showing water stress tolerance. The results also show that a water deficit was associated with reduced biotic stress responses. Additionally, heat shock protein genes were differentially expressed in all clones except for highly susceptible Cardinal. Together, the gene expression study demonstrates variation in the molecular pathways and biological processes in response to water stress contributing to tolerance and susceptibility. [ABSTRACT FROM AUTHOR]

Isolating RNA from dry conifer seeds can be difficult because of a number of interfering compounds present in seeds. We describe a protocol for total RNA isolation from black spruce dry seeds, which is an adaptation of a method used for mouse myeloma tissues. The extraction relies on selective precipitation of RNA by using lithium chloride. [ABSTRACT FROM AUTHOR]