| Heracleum moellendorffii Hance is a perennial herbaceous herb of the Umbelliferae family,and it belongs to Heracleum L,which is also known as mountain celery,short fruit celery and largeleaved celery.Heracleum moellendorffii Hance is mostly distributed in shaded place.Heracleum moellendorffii Hance is a mountain wild vegetable that is used for both medicine and food.The seeds of Heracleum moellendorffii Hance have dormancy characteristics.Due to the dormancy characteristics of Heracleum moellendorffii Hance seeds,some problems are encountered in the production such as lower and irregular germination rate,and longer periods of seedling growth,etc.In order to deal with these problems,seeds harvested in summer were used as materials for maturity research.In this study,the difference of seeds maturity between the central and outer seeds of the ears were compared.Seeds weight distribution were explored.Seed morphology,embryo morphological indexes and embryo development among different shade-dried seeds weight were measured.Furthermore,the correlation among different indicators were analyzed.Low-temperature stratification can promote Heracleum moellendorffii Hance seeds germination.To better understand proteomic changes during stratification,tandem mass tag(TMT)mass spectrometry(MS)/MS was used to detect significant changes in protein accumulated among nonstratified seeds(NS),cotyledon stage embryo seeds(CS)and germinated seeds(GS).The main results were as followed:(1)The seeds of Heracleum moellendorffii Hance have post-ripening phenomenon,and the seed embryos are not fully developed when harvesting.At the time of harvest,the embryos of Heracleum moellendorffii Hance were mainly in the period of heart-shaped embryo and torpedo-shaped embryo,in which the seeds in the late heart-shaped embryo were the highest.(2)100-grain weight of outside the ears are heavier than the central seeds of the ears,and the maturity is higher.Higher weight seeds have higher degree of embryo development and greater embryo rate.(3)A total of 876 proteins were identified among three samples during stratification,502 of which were differentially accumulated.Eighty-six proteins were differentially accumulated between nonstratified seeds and cotyledon stage embryo seeds,278 proteins were differentially accumulated between germinated seeds and nonstratified seeds,and 414 proteins were differentially accumulated between cotyledon stage embryo seeds and germinated seeds.(4)The differentially accumulated proteins were described by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses.The results showed that these proteins are mostly enzymes with binding and catalytic activity.Metabolic processes and stress responses were the biological processes in which these proteins are primarily involved.Different proteins are involved in carbohydrate metabolism and ribosome pathways.And UTP--glucose-1-phosphate uridylyltransferase,sucrose synthase,glycogen phosphorylase,malate dehydrogenase,3-ketoacylCoA thiolase 2,fatty acid beta-oxidation multifunctional protein,40 S ribosomal protein S5,60 S ribosomal protein L23 and 60 S acidic ribosomal protein P2 were key proteins for these terms.Obtain the gene sequences corresponding to these proteins in the NCBI database for qRT-PCR verification.The trend of the accumulation of most proteins are consistent with the expression level of their coding genes.(5)Using Wolfpsort software to predict the subcellular localization of the identified proteins,it was found that the proteins of the seed stratification were mainly located in the cytoplasm(41.05%),plastid(15.27%),nucleus(7.78%),mitochondria(5.19%),secretions(5.19%),endoplasmic reticulum(3.46%)and other locations. |
