Cryptochrome 2 from Lilium × formolongi Regulates Photoperiodic Flowering in Transgenic Arabidopsis thaliana.

The photoperiodic flowering pathway is essential for plant reproduction. As blue and ultraviolet-A light receptors, cryptochromes play an important role in the photoperiodic regulation of flowering. Lilium × formolongi is an important cut flower that flowers within a year after seed propagation. Floral induction is highly sensitive to photoperiod. In this study, we isolated the CRYPTOCHROME2 gene (LfCRY2) from L. × formolongi. The predicted LfCRY2 protein was highly homologous to other CRY2 proteins. The transcription of LfCRY2 was induced by blue light. LfCRY2 exhibits its highest diurnal expression during the floral induction stage under both long-day and short-day photoperiods. Overexpression of LfCRY2 in Arabidopsis thaliana promoted flowering under long days but not short days, and inhibited hypocotyl elongation under blue light. Furthermore, LfCRY2 was located in the nucleus and could interact with L. × formolongi CONSTANS-like 9 (LfCOL9) and A. thaliana CRY-interacting basic-helix-loop-helix 1 (AtCIB1) in both yeast and onion cells, which supports the hypothesis that LfCRY2 hastens the floral transition via the CIB1-CO pathway in a manner similar to AtCRY2. These results provide evidence that LfCRY2 plays a vital role in promoting flowering under long days in L. × formolongi.

Functional and Evolutionary Characterization of the CONSTANS-like Family in Lilium�formolongi.

Lilium�formolongi is a facultative long-day (LD) plant. Aiming to dissect the molecular regulation of the photoperiodic pathway, largely unknown in Lilium, we explored the CONSTANS/FLOWERING LOCUS T (CO/FT) module, a major regulatory factor in the external coincidence model of the photoperiodic flowering pathway in lily. We identified eight CONSTANS-LIKE (COL) family members in L.�formolongi, which could be divided into three types, according to their zinc-finger (B-box) protein domains. Type I included only LfCOL5, containing two B-box motifs. Type II contained six LfCOLs members that had only one B-box motif. Type III contained only LfCOL9 that showed a normal B-box and a second divergent B-box motif. Phylogenic analyses revealed that LfCOL5 was the closest to Arabidopsis CO. LfCOL5, LfCOL6 and LfCOL9 were up-regulated at the flowering induction stage under LDs, coinciding with an increase in LfFT1 expression. LfCOL5, LfCOL6 and LfCOL9 also showed obvious diurnal expression pattern for 3 d under LDs. However, under short-day (SD) conditions, the expression patterns of LfCOL5, LfCOL6 and LfCOL9 were variable and complex, with regard to the developmental stages and circadian rhythm. LfCOL5, LfCOL6 and LfCOL9 complemented the late flowering phenotype of the co mutant in Arabidopsis. Taken together, the results suggest that LfCOL5, LfCOL6 and LfCOL9 are involved in triggering flowering induction under LDs. LfCOL6 and LfCOL9 belong to types different from functional COL homologs in other plant species, illustrating the variation in phylogeny, evolution and gene function among LfCOL family members.

Analysis of global gene expression profiles during the flowering initiation process of Lilium × formolongi.

The onset of flowering is critical for the reproductive development of plants. Lilium × formolongi is a lily hybrid that flowers within a year after sowing. We successfully identified four important stages during vegetative growth and flowering initiation of L. × formolongi under long day conditions. The plant tissues from the four stages were used in a genome-wide transcriptional analysis to investigate stage-specific changes of gene expression in L. × formolongi. In total, the sequence reads of the four RNA-sequencing libraries were assembled into 52,824 unigenes, of which 37,031 (70.10%) were differentially expressed. The global expression dynamics of the differentially expressed genes were predominant in flowering induction phase I and the floral differentiation stage, but down-regulated in flowering induction phase II. Various transcription factor families relevant to flowering were elucidated, and the members of the MADS-box, SBP and CO-like transcription factor families were the most represented. There were 85 differentially expressed genes relevant to flowering. CONSTANS-LIKE, FLOWERING LOCUS T, TREHALOSE-6-PHOSPHATE SYNTHASE and SQUAMOSA PROMOTER BINDING PROTEIN-LIKE homologs were discovered and may play significant roles in the flowering induction and transition process of L. × formolongi. A putative gene regulatory network, including photoperiod, age-dependent and trehalose-6-phosphate flowering pathways, was constructed. This is the first expression dataset obtained from a transcriptome analysis of photoperiod-mediated flowering pathway in lily, and it is valuable for the exploration of the molecular mechanisms of flowering initiation and the short vegetative stage of L. × formolongi.

Formal nucleophilic pyrrolylmethylation via palladium-based auto-tandem catalysis: switchable regiodivergent synthesis and remote chirality transfer.

Although nucleophilic benzylation-type reaction to introduce various aromatic systems into molecules has been widely explored, the related pyrrolylmethylation version remains to be disclosed. Reported herein is a palladium-catalysed multiple auto-tandem reaction between N-Ts propargylamines, allyl carbonates and aldimines in the presence of an acid, proceeding through sequential allylic amination, cycloisomerisation, vinylogous addition and aromatisation steps. A diversity of formal pyrrolylmethylated amine products were finally furnished efficiently. In addition, switchable regiodivergent 3-pyrrolylmethylation and 4-pyrrolylmethylation were realised by tuning catalytic conditions. Moreover, remote chirality transfer with readily available enantioenriched starting materials was well achieved with an achiral ligand, relying on diastereoselective generation of η2-Pd(0) complexes between Pd(0) and chiral 1,3-diene intermediates in the key vinylogous addition step. A few control experiments were conducted to elucidate the palladium-involved tandem reaction and regiodivergent synthesis.

Molecular cloning of cryptochrome 1 from Lilium×formolongi and the characterization of its photoperiodic flowering function in Arabidopsis.

Lilium × formolongi is an important cut flower species that is able to flower within a year following seed propagation, with flower induction that is very sensitive to the photoperiod. Cryptochromes are blue/UV-A light receptors that regulate many important plant growth and development processes, including photoperiodic flowering. In this study, we isolated the cryptochrome 1 (CRY1) gene from L. × formolongi and analyzed its function in transgenic Arabidopsis. The predicted LfCRY1 protein was strongly homologous to other CRY1 proteins. The transcription of LfCRY1 was induced by blue light, with LfCRY1 exhibiting its highest expression and diurnal expression patterns during the flowering-induction stage under both long-day (LD) and short-day (SD) photoperiods. Overexpression of LfCRY1 in Arabidopsis promoted flowering under LDs but not SDs and inhibited hypocotyl elongation under blue light. The LfCRY1 protein was located in both the nucleus and cytoplasm. LfCRY1 interacted with the important flowering activator LfCOL9 in both yeast and onion cells. These results provide functional evidence for the role of LfCRY1 in controlling photoperiodic flowering under LDs and indicate that LfCRY1 may be a counterpart of AtCRY1. Understanding the role of LfCRY1 in photoperiodic flowering is beneficial for the molecular breeding of lilies with shorter vegetative stages.

Prenatal diagnose of a fetus with Harlequin ichthyosis in a Chinese family.

OBJECTIVE: Harlequin ichthyosis (HI) was the most severe form of ichthyoses, which leaded to neonatal death in 50% of cases. It was the result of mutations in ABCA12 gene. With the development of ultrasound skills and genetic analysis, HI could be prenatal diagnosed. CASE REPORT: Here, we reported a case of HI, which was prenatal diagnosed by ultrasound examination and genetic analysis. The fetus was found that severe ectropion, eclabium, flattened nose, and rudimentary ears by ultrasound at 20 weeks gestation. A molecular genetic analysis was performed and revealed two mutations in the ABCA12 gene. One of two mutations were not reported in the past. The fetus was terminated. CONCLUSION: HI was associated with the poor prognosis of HI neonates. Prenatal ultrasound and genetic analysis were important for prenatal diagnosis of HI and were helpful to give sufficient prenatal counsels for the family with HI baby.