Genome-Wide Identification and Expression Analysis of the Phytocyanin Gene Family in Nicotiana tabacum

Phytocyanin(PC)is a class of plant-specific blue copper proteins involved in electron transport,plant growth,development,and stress resistance.However,PC proteins have not been systematically evaluated in tobacco plants.We determined the whole-genome sequences of the PC family in the tobacco cultivar‘K326.’The transcriptome data were used to analyze the expression of the NtPC family at different development stages and tissue-specific genes.Real-time fluorescence quantitative analysis was used to analyze the expression of the NtPC gene family under low temperature and methyl jasmonate stress.The tobacco NtPC family contained 110 members and was divided into four subfamilies:early nodulin-like protein(NtENODL),uclacyanin-like protein,stellacyanin1-like protein,and plantacyanin-like protein.According to phylogenetic and structural analyses,the NtPC family could be divided into eight structural types.Fifty-three NtPCs were randomly distributed on 22 of 24 tobacco chromosomes.Collinearity analysis revealed 33 pairs of genes belonging to the NtPC family.Gene ontology analysis showed that the PC genes are components of the plasma membrane and may participate in plasma membrane-related functions.The NtPC family contained numerous elements related to hormonal and abiotic stress responses and was specifically expressed in the tobacco prosperous,maturation,and budding periods.Tissue-specific expression analysis showed that some genes were tissue specific.The expression of NtENODL58 and other genes was significantly induced by low-temperature and methyl jasmonate stress.Thus,the NtPC gene family plays an important role in plant stress response.

Expression and Interaction Analysis of FAZ1 Protein in Brassica oleracea

To identify and characterize genes involved in reproductive tissue abscission in Brassica oleracea,the transcript data of pollinated pistil was analyzed.A differentially expressed gene,named BoFAZ1(FLOWER ABSCISSION ZONE1)was identified,which contains one exon and encompass a 139aa.Furthermore,a T-DNA insertion mutant(SALK_302_G01)(faz1 mutant)was obtained from Arabidopsis thaliana mutant library.Floral organ shedding from mutants was delayed and a V-shaped structure in the boundary region between the stalk and torus of the sepal abscission zone was obtained in faz1 mutant.The cell density of this structure was lower than that of the corresponding region in the wild-type control.In the transgenic plants,the normal development of the stalk zone of faz1 was recovered completely by transforming a 1919-bp DNA fragment of BoFAZ1 into the faz1 mutant.In Addition,our data showed that BoFAZ1 was expressed in mature pollen grains,but not in the bracts,roots,stems,leaves,and sepals.Its expression in the filaments,stigma,and pistil exfoliation layer gradually increased after pollination.Subcellular localization experiments showed that BoFAZ1 was located in the cell membrane.A myristoylation site was found at the N-terminus of BoFAZ1.Removal of this site resulted in protein dislocation in the cytoplasm,cell membrane and nucleus.Finally,a yeast two-hybrid test indicated that BoH3.2(histone H3.2),a protein involved in abscission zone development,interacted with BoFAZ1.This interaction was verified by a GST pull-down assay.In summary,our data indicated that BoFAZ1 was involved in the formation of the pistil abscission zone in B.oleracea.