Overexpression of the Transcription Factor Improves Transformation of Dicot and Monocot Species.

Successful regeneration of genetically modified plants from cell culture is highly dependent on the species, genotype, and tissue-type being targeted for transformation. Studies in some plant species have shown that when expression is altered, some genes regulating developmental processes are capable of triggering plant regeneration in a variety of plant cells and tissue-types previously identified as being recalcitrant to regeneration. In the present research, we report that developmental genes encoding GROWTH-REGULATING FACTORS positively enhance regeneration and transformation in both monocot and dicot species.

Laser-Capture Microdissection of Maize Kernel Compartments for RNA-Seq-Based Expression Analysis.

Laser-capture microdissection (LCM) enables isolation of single cells or groups of cells for a variety of downstream applications including transcriptome profiling. Recently, this methodology has found a more widespread use particularly with the advent of next-generation sequencing techniques that enable deep profiling of the limited amounts of RNA obtained from fixed or frozen sections. When used with fixed tissues, a major experimental challenge is to balance the tissue integrity needed for microscopic visualization of the cell types of interest with that of the RNA quality necessary for deep profiling.

A part of the upstream promoter region of SHN2 gene directs trichome specific expression in Arabidopsis thaliana and heterologous plants.

A promoter trap mutant line of Arabidopsis carrying a promoterless β-glucuronidase (uidA) gene exhibited GUS expression predominantly in all the trichomes. In this mutant, the T-DNA insertion was localized at 147bp upstream of the putative start codon, ATG, of the At5g11190 (SHN2) gene. Transcript profiling of the SHN2 suggested a constitutive expression of the gene in all the tissues.

Aflatoxin-free transgenic maize using host-induced gene silencing.

Aflatoxins, toxic secondary metabolites produced by some species, are a universal agricultural economic problem and a critical health issue. Despite decades of control efforts, aflatoxin contamination is responsible for a global loss of millions of tons of crops each year. We show that host-induced gene silencing is an effective method for eliminating this toxin in transgenic maize.

RNA-Seq analysis of laser-capture microdissected cells of the developing central starchy endosperm of maize.

Endosperm is a product of double fertilization, and provides nutrients and signals to the embryo during seed development in flowering plants. Early stages of endosperm development are critical for the development of its storage capacity through synthesis and accumulation of starch and storage proteins. Here we report on the isolation and sequencing of mRNAs from the central portion of the starchy endosperm of Zea mays (maize) B73 at 6 days after pollination.

RNA sequencing of laser-capture microdissected compartments of the maize kernel identifies regulatory modules associated with endosperm cell differentiation.

Endosperm is an absorptive structure that supports embryo development or seedling germination in angiosperms. The endosperm of cereals is a main source of food, feed, and industrial raw materials worldwide. However, the genetic networks that regulate endosperm cell differentiation remain largely unclear.

The alleles at the E1 locus impact the expression pattern of two soybean FT-like genes shown to induce flowering in Arabidopsis.

A small gene family of phosphatidyl ethanolamine-binding proteins (PEBP) has been shown to function as key regulators in flowering; in Arabidopsis thaliana the FT protein promotes flowering whilst the closely related TFL1 protein represses flowering. Control of flowering time in soybean [Glycine max (L.) Merrill] is important for geographic adaptation and maximizing yield.

Expression of flowering-time genes in soybean E1 near-isogenic lines under short and long day conditions.

Control of soybean flowering time is important for geographic adaptation and maximizing yield. Plant breeders have identified a series of genes (E genes) that condition time to flowering; however, the molecular basis in the control of flowering by these E genes, in conjunction with canonical flowering-time genes, has not been studied. Time to flowering in near-isogenic lines (NILs) at the E1 locus was tested using a reciprocal transfer experiment under short day (SD) and long day (LD) conditions.

The MADS-domain transcriptional regulator AGAMOUS-LIKE15 promotes somatic embryo development in Arabidopsis and soybean.

The MADS-domain transcriptional regulator AGAMOUS-LIKE15 (AGL15) has been reported to enhance somatic embryo development when constitutively expressed. Here we report that loss-of-function mutants of AGL15, alone or when combined with a loss-of-function mutant of a closely related family member, AGL18, show decreased ability to produce somatic embryos. If constitutive expression of orthologs of AGL15 is able to enhance somatic embryo development in other species, thereby facilitating recovery of transgenic plants, then AGL15 may provide a valuable tool for crop improvement.

T-DNA tagging and characterization of a cryptic root-specific promoter in Arabidopsis.

From a T-DNA tagged Arabidopsis population, a line, M-57 showing GUS (beta-glucuronidase) expression in the vascular regions of young roots was identified. Southern analysis revealed presence of a single T-DNA insert. Using inverse PCR, the plant sequence flanking the T-DNA insertion was cloned.

Cloning and characterization of a pentatricopeptide protein encoding gene (LOJ) that is specifically expressed in lateral organ junctions in Arabidopsis thaliana.

A line exhibiting expression of beta-glucuronidase (GUS) in the lateral organ junctions and shoot apical meristem (SAM) was identified from a population of T-DNA tagged lines carrying a promoter-less GUS gene. Southern hybridization confirmed the presence of a single T-DNA insertion in this line. The plant sequences flanking the T-DNA were cloned by TAIL PCR and sequenced.