Cloning and characterization of geranylgeranyl diphosphate synthetase from Pinus massoniana and its correlation with resin productivity

Geranylgeranyl pyrophosphate synthetase(GGPPS) has gained increasing attention as a key enzyme in terpene analysis.We designed specific primers based on plant GGPPS homologs and used reverse transcription polymerase chain reaction(RT-PCR) to obtain and identify Pin GGPPS,a GGPPS gene sequence from Pinus massoniana,using bioinformatics tools.Quantitative PCR analysis of Pin GGPPS expression levels in roots,pine needles,immature stems,and semilignified stems from 6-month-old P.massoniana showed that expression levels of Pin GGPPS were highest in pine needles,followed by immature stems and semilignified stems,and lowest in roots.When we examined the correlation between Pin GGPPS gene expression levels and resin productivity in 20 adult plants for 28 successive days,Pin GGPPS expression levels presented a substantially linear distribution when plotted against their corresponding resin yields.In summary,we characterized the gene Pin GGPPS for the first time in P.massoniana,and established a correlation between Pin GGPPS gene expression levels and resin productivity,suggesting the importance of theory and production practice for P.massoniana.

Evolutionary and paleobiological implications of Coleoptera (Insecta) from Tethyan-influenced Cretaceous ambers

The intense study of coleopteran inclusions from Spanish （Albian in age） and French （Albian-Santonian in age） Cretaceous ambers, both of Laurasian origin, has revealed that the majority of samples belong to the Polyphaga suborder and, in contrast to the case of the compression fossils, only one family of Archostemata, one of Adephaga, and no Myxophaga suborders are represented. A total of 30 families from Spain and 16 families from France have been identified （with almost twice bioinclusions identified in Spain than in France）; 13 of these families have their most ancient representatives within these ambers. A similar study had previously only been performed on Lebanese ambers （Barremian in age and Gondwanan in origin）, recording 36 coleopteran families. Few lists of taxa were available for Myanmar （Burmese） amber （early Cenomanian in age and Laurasian in origin）. Coleopteran families found in Cretaceous ambers share with their modern relatives mainly saproxylic and detritivorous habits in the larval or adult stages, rather than wood-boring behavior. Fifteen of the coleopteran families occur in both the Lebanese and Spanish ambers; while only five are present in both Spanish and French. Considering the paleogeographic proximity and similarity of age of the Spanish and French ambers, the small number of taxa found in common at both areas is surprising. The ancient origin for the Lebanese and Spanish ambers, the paleogeography （including some barriers for terrestrial biota） and the local paleohabitats are factors that may explain the dissimilarity with the French specimens. Wildfires are believed to be a more likely cause of resin production during the Cretaceous than infestation by beetles. Current knowledge of the beetle species found in the Cretaceous ambers is introduced.

Formation of Hybrid Ring Structure of Cyanurate/Isocyanurate in the Reaction be-tween 2,4,6-Tris(4-Phenyl-Phenoxy)-1, 3,5-Triazine and Phenyl Glycidyl Ether

Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.