Sequence Characterization and Spatiotemporal Expression Patterns ofPbS₂₆-RNaseGene in Chinese White Pear (Pyrus bretschneideri)

Abstract

Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cultivar “Hongpisu.” The cDNA sequence for PbS 26 -RNase was deposited in GenBank under accession number EU081888. At the amino acid level, the PbS 26 -RNase displayed the highest similarity (96.9%) with PcSa-RNase of P. communis, and only seven amino acid differences were present in the two S-RNases. Phylogenetic analysis of rosaceous S-RNases indicated that the PbS 26 -RNase clustered with maloideous S-RNases, forming a subfamily-specific not a species-specific group. The PbS 26 -RNase gene was specifically expressed in the style but not other tissues/organs. The expression level of the PbS 26 -RNase gene rapidly increased at bell balloon stage (BBS), and then it dropped after pollination. However, the abundance of the PbS 26 -RNase gene transcript in the style was greater after cross-pollination than after self-pollination. In addition, a method for rapidly detecting the PbS 26 -RNase gene was developed via allele-specific primers design. The present study could provide a scientific basis for fully clarifying the mechanism of pear SI at the molecular level.

Proteomic Analysis of the Inflorescence Stem Mechanical Strength Difference in Herbaceous Peonies (Paeonia lactiflora Pall.)

“… 24 The irreversible UDP-glucuronate in UXS produces UDP-xylose, which is the nucleotide sugar necessary for araboxylan, arabinogalactan proteins, and pectic polysaccharide in the cell wall. 25 CAD is one of the key enzymes during the synthesis of lignin and can catalyze the precursor to generate a lignin monomer, such as coumaric aldehyde, sinaldehyde, or coniferyl aldehyde. 26 Polysaccharide is the main chemical component of the cell wall and can provide mechanical support for the plant stem.…”

“…First, the expression abundance of UDP-glucuronate decarboxylase and cinnamyl alcohol dehydrogenase in this study researching the proteins related to the carbohydrate metabolism is large in “Taoli Yanzhuang” with high mechanical strength, which implies that the level of carbohydrate metabolism is high in “Taoli Yanzhuang” . The irreversible UDP-glucuronate in UXS produces UDP-xylose, which is the nucleotide sugar necessary for araboxylan, arabinogalactan proteins, and pectic polysaccharide in the cell wall . CAD is one of the key enzymes during the synthesis of lignin and can catalyze the precursor to generate a lignin monomer, such as coumaric aldehyde, sinaldehyde, or coniferyl aldehyde .…”