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Backgrounds: Aglaonema commutatum ‘Red Valentine’, as an excellent foliage ornamental plant, is widely used in interior and exterior decoration because of its easy cultivation and management. However, reducing proportions of red color foliage during large-scale production of A. commutatum seedlings is of frequent occurence, which has considerable implications on the ornamental and market value of the plant, and the molecular mechanisms of this phenomenon remain unclear. Results: To explore the molecular basis leading to the variation in leaf color in A. commutatum ‘Red Valentine’, transcriptome sequencing were performed based on the Illumina platform in two different varieties at three leaf developmental stages. We annotated 63621 unigenes and 14186 differentially expressed genes by pairwise comparison. Further, twenty-six anthocyanin biosynthetic structural genes were identified, the PKM values were significantly higher in ‘Red Valentine’ than those in the green mutant at the three stages examined, which is consistent with the high anthocyanin content of‘Red Valentine’ leaves. Positive transcription factors that may involved in regulating anthocyanin biosynthesis were detected by BLAST tool and correlation analysis and a downregulation of these TFs may downregulate the expression of anthocyanin genes. Full-length cDNA of anthocyanin biosynthesis and regulation genes was obtained and phylogenetic trees were performed to ensure the accuracy of the analysis. Conclusion: Our study provide an insight into the further understanding of leaf variation and facilitate the breeding of ornamental cultivars with high-anthocyanins levels in A. commutatum ‘Red Valentine’.

Euryodendron excelsum H.T. Chang is a first class of rare and endangered woody plant endemic to China. Leaves and petioles from the axillary shoots in vitro were used as explants to culture on the different PGR WPM medium and establish an efficient shoot proliferation and plant regeneration system. Callus and 3–6 adventitious shoots or somatic embryos were induced. WPM supplemented with 1.0 mg/L 2,4-D induced callus that then dedifferentiated into shoots and somatic embryos on different media, including PGR-free WPM. However, only adventitious shoots formed on WPM with 1.0 mg/L of cytokinins, 6-benzyladenine (BA), kinetin (KIN) or thidiazuron (TDZ). When another cytokinin, zeatin, was used, somatic embryos were induced directly from leaves and petioles. Adventitious roots could be induced from both explants on WPM with 1.0 mg/L α-naphthaleneacetic acid (NAA). Somatic embryos cultured in PGR-free WPM or WPM with 0.2 mg/L NAA developed roots. Plantlets derived from somatic embryos were transferred to a peat: sand (1:1, v/v) substrate, with 64.3% survival after 30 d, and 54.6% after 90 d. Callus clumps with adventitious shoot buds that were transferred to WPM with 1.0 mg/L BA and 0.2 mg/L NAA developed mean 3.3 multiple shoots. Callus-derived shoots regenerated and rooted successfully (100%) on agar-free vermiculite-based WPM with 0.5 µM NAA after 30 d. Plantlets transplanted to peat soil: vermiculite (1:1, v/v) displayed highest survival (96.7%) after three months. This protocol allows for the mass propagation of tissue-cultured plants and the conservation of this rare and endangered genetic resource.

Thermos-sensitive genic male sterility (TGMS) is the important genetic resource in two-line hybrid rice breeding. The pollen fertility of TGMS lines is regulated by a single point mutation on the TGMS genes. Based on the single nucleotide polymorphism (SNP) and indel, KASP markers were developed and utilized in rice molecular breeding due to high-through detection with low cost and save time. In this study, we convert the SNPs on TGMS genes including p/tms12-1 and tms9-1 gene to the functional co-dominant KASP marker and used in two-line hybrid rice breeding. We can differentiate the TGMS lines conferring p/tms12-1 or tms9-1 from another TGMS lines by KASP assay. Of them, the genotype of Pei'ai64S and Hua201S containing p/tms12-1 is homozygous GG genotype with blue signal, and the genotype of HengnongS-1 containing tms9-1 is homozygous CC genotype with red signal. KASP assay for tms9-1 gene was proved that the genetic mode is fit to one recessive Mendalian trait. The test of seed purity was performed by KASP marker for the two-line hybrid varieties of Liangyoupeijiu and Hualiangyou1206, which is consistent with the previous dCAPS marker. Moreover, the tms12-1 and tms9-1 gene were pyramided in the same genetic background and the new TGMS lines were generated. Therefore, the KASP marker for TGMS genes developed in this study can be widely used in two-line hybrid rice breeding. It will provide a visual convenient toolkit for breeders to select the target individual plant by the high-throughput detection in the different two-line rice breeding program.

Sandalwood is highly valued for its fragrant heartwood and its extracted oil. The major oil component santalols are terpenoids, which are biosynthesis through the MVA pathway. MK and PMK are the major enzymes on the MVA pathway. Little is known about the genes encoding MK and PMK in Santalum album on its expression regulation mechanism. The analysis of MK and PMK genes and their functions are important for the further study of the biosynthesis of santalol. These results will help to further study the role of MK and PMK genes in S. album santalol biosynthesis. The total RNA of sandalwood leaves was extracted, then the First-strand cDNA synthesis was obtained through the PrimeScript first-strand cDNA synthesis kit. Then sequence comparison and bioinformatics analyses of the genes homology of SaMK and SaPMK with MKs and PMKs, We also investigated subcellular localization of SaMK and SaPMK proteins. Its functional complementation of SaMK and SaPMK in yeast were also investigated. Atlast, MeJA was used to induce tissue-specific analysis and expression profiles of SaMK and SaPMK. The results showed that the full-length cDNA sequences of SaMK and SaPMK were 1409 bp and 1679 bp containing a 1381 bp open reading frame (ORF) encoding a polypeptide of 460 amino acids and a 1527 bp ORF encoding a polypeptide of 508 amino acids, respectively. Sequence comparison and bioinformatics analyses indicated that SaMK and SaPMK showed high homology with MKs and PMKs, respectively from other plant species. Further functional complementation of SaMK in an MK-deficient mutant yeast strain YMR208W and SaPMK in a PMK-deficient mutant yeast strainYMR220W confirmed that cloned SaMK and SaPMK cDNA encode a functional MK and PMK, respectively and mediated MVA biosynthesis in yeast. Tissue expression pattern analysis revealed that SaMK and SaPMK were constitutively expressed in all the tested tissues. SaMK was highly expressed in young leaves but least expressed in sapwood while SaPMK was highly expressed in roots and mature leaves, and least expressed in young leaves.

Background: WRKY proteins are a large superfamily of transcription factors that are involved in diverse biological processes including development, as well as biotic and abiotic stress responses in plants. WRKY family proteins have been extensively characterized and analyzed in many plant species, including Arabidopsis , rice and poplar. However, knowledge on WRKY transcription factors in S antalum album is scarce. Results: Based on S . albu m genome and transcriptome data, 64 SaWRKY genes were identified in this study. A phylogenetic analysis based on the structures of WRKY protein sequences divided these genes into three major groups (I, II, III) together with WRKY protein sequences from Arabidopsis . Tissue-specific expression patterns showed that 37 SaWRKY genes were expressed in at least one of five tissues (leaves, roots, heartwood, sapwood, or the transition zone) while the remaining four genes were weakly expressed in all of these tissues. Analysis of the expression profiles of the 42 SaWRKY genes after callus was stimulated by salicylic acid (SA) and methyl jasmonate (MeJA) revealed that 34 and 19 SaWRKY genes, respectively were significantly induced. The function of SaWRKY1 , which was significantly up-regulated by SA and MeJA, was analyzed. SaWRKY1 was localized in the nucleus and its overexpression improved salt tolerance in transgenic Arabidopsis . Conclusions: Our study provides important information to further identify the functions of SaWRKY genes and to understand the roles of SaWRKY family genes involved in development and in SA- and MeJA-mediated stress responses.

Background: Fahr’s disease is a rare neurological disorder which is characterized by diffuse intracranial calcification documented in bilateral basal ganglia and dentate nuclei of the cerebellum. In recent years, some acute presentations of Fahr’s disease have been reported. Here we describe a Fahr’s disease patient presenting with thalamic hemorrhage, which has not been reported so far. Case presentation: A 51-year-old man doesn’t have any prior premonitory symptoms and significant family history of neurologic disorder, he presented to our emergency department because of acute left limb numbness. Both brain CT and MRI study exhibited symmetric calcifications in bilateral basal ganglia and bilateral cerebellar dentate nuclei, which was consistent with Fahr’s disease. In addition, the blood investigation provided no criteria to secondary intracranial calcification. After proper clinical medical treatment and sustained physical rehabilitation, the patient’s symptoms relieved and he was discharged from hospital. Conclusion: We describe a case of sporadic Fahr’s disease presenting with thalamic hemorrhage. It is unknown whether the calcification in Fahr’s disease negatively affects intracranial vessels predisposing acute presentation. Therefore, the association between idiopathic basal ganglia calcification and acute cerebrovascular disease is worth special attention and needs further studies. Keywords: Fahr’s disease, thalamic hemorrhage.