A pollen-specific calmodulin-binding protein, NPG1, interacts with putative pectate lyases.

Previous genetic studies have revealed that a pollen-specific calmodulin-binding protein, No Pollen Germination 1 (NPG1), is required for pollen germination. However, its mode of action is unknown. Here we report direct interaction of NPG1 with pectate lyase-like proteins (PLLs).

Interactions of SR45, an SR-like protein, with spliceosomal proteins and an intronic sequence: insights into regulated splicing.

SR45 is a serine/arginine-rich (SR)-like protein with two arginine/serine-rich (RS) domains. We have previously shown that SR45 regulates alternative splicing (AS) by differential selection of 5' and 3' splice sites. However, it is unknown how SR45 regulates AS.

Tobacco as a production platform for biofuel: overexpression of Arabidopsis DGAT and LEC2 genes increases accumulation and shifts the composition of lipids in green biomass.

When grown for energy production instead for smoking, tobacco can generate a large amount of inexpensive biomass more efficiently than almost any other agricultural crop. Tobacco possesses potent oil biosynthesis machinery and can accumulate up to 40% of seed weight in oil. In this work, we explored two metabolic engineering approaches to enhance the oil content in tobacco green tissues for potential biofuel production.

Plant-produced hepatitis B core protein chimera carrying anthrax protective antigen domain-4.

The hepatitis B core antigen (HBcAg) can generate a strong immune response and is recognized as an effective carrier for foreign epitopes. The domain-4 epitope of the anthrax protective antigen (PA-D4) plays an essential role in generating protective immunity against virulent Bacillus anthracis. Here we report the successful production of a recombinant protein comprised of the antigenic PA-D4 integrated into the c/e1 loop of HBcAg in transgenic low-alkaloid Nicotiana tabacum.

Immunogenic properties of plant-derived recombinant smallpox vaccine candidate pB5.

The extracellular virion membrane protein B5 is a potent inducer of immune responses capable of protecting mice and primates against poxvirus infections. Here, we examined the antibody response induced in mice immunized intramuscularly (i.m.

Regulation of plant developmental processes by a novel splicing factor.

Serine/arginine-rich (SR) proteins play important roles in constitutive and alternative splicing and other aspects of mRNA metabolism. We have previously isolated a unique plant SR protein (SR45) with atypical domain organization. However, the biological and molecular functions of this novel SR protein are not known.

Organ-specific, developmental, hormonal and stress regulation of expression of putative pectate lyase genes in Arabidopsis.

Pectate lyases catalyse the eliminative cleavage of de-esterified homogalacturonan in pectin, a major component of the primary cell walls in higher plants. In the completed genome of Arabidopsis, there are 26 genes (AtPLLs) that encode pectate lyase-like proteins. Here, we analysed the expression pattern of all AtPLLs in different organs, at different stages of seedling development and in response to various hormones and stresses.

Smallpox subunit vaccine produced in Planta confers protection in mice.

We report here the in planta production of the recombinant vaccinia virus B5 antigenic domain (pB5), an attractive component of a subunit vaccine against smallpox. The antigenic domain was expressed by using efficient transient and constitutive plant expression systems and tested by various immunization routes in two animal models. Whereas oral administration in mice or the minipig with collard-derived insoluble pB5 did not generate an anti-B5 immune response, intranasal administration of soluble pB5 led to a rise of B5-specific immunoglobulins, and parenteral immunization led to a strong anti-B5 immune response in both mice and the minipig.

Plant-derived anti-Lewis Y mAb exhibits biological activities for efficient immunotherapy against human cancer cells.

Although current demands for therapeutic mAbs are growing quickly, production methods to date, including in vitro mammalian tissue culture and transgenic animals, provide only limited quantities at high cost. Several tumor-associated antigens in tumor cells have been identified as targets for therapeutic mAbs. Here we describe the production of mAb BR55-2 (IgG2a) in transgenic plants that recognizes the nonprotein tumor-associated antigen Lewis Y oligosaccharide overexpressed in human carcinomas, particularly breast and colorectal cancers.

Severe acute respiratory syndrome (SARS) S protein production in plants: development of recombinant vaccine.

In view of a recent spread of severe acute respiratory syndrome (SARS), there is a high demand for production of a vaccine to prevent this disease. Recent studies indicate that SARS-coronavirus (CoV) spike protein (S protein) and its truncated fragments are considered the best candidates for generation of the recombinant vaccine. Toward the development of a safe, effective, and inexpensive vaccine candidate, we have expressed the N-terminal fragment of SARS-CoV S protein (S1) in tomato and low-nicotine tobacco plants.

Nuclear localization and in vivo dynamics of a plant-specific serine/arginine-rich protein.

Serine/arginine-rich (SR) proteins in non-plant systems are known to play important roles in both constitutive and alternative splicing of pre-messenger RNAs (pre-mRNAs). Recently, we isolated a novel SR protein (SR45), which interacts with U1 snRNP 70K protein, a key protein involved in 5' splice site recognition. SR45 is found only in plants and is unique in having two SR domains separated by an RNA recognition motif (RRM).

A calmodulin-binding protein from Arabidopsis has an essential role in pollen germination.

Calmodulin (CaM), a ubiquitous multifunctional calcium sensor in all eukaryotes, mediates calcium action by regulating the activity/function of many unrelated proteins. Although calcium and CaM are known to play a crucial role in pollen germination and pollen tube growth, the proteins that mediate their action have not been identified. We isolated three closely related CaM-binding proteins (NPG1, NPGR1, and NPGR2) from Arabidopsis.

Expression of U1 small nuclear ribonucleoprotein 70K antisense transcript using APETALA3 promoter suppresses the development of sepals and petals.

U1 small nuclear ribonucleoprotein (snRNP)-70K (U1-70K), a U1 snRNP-specific protein, is involved in the early stages of spliceosome formation. In non-plant systems, it is involved in constitutive and alternative splicing. It has been shown that U1snRNP is dispensable for in vitro splicing of some animal pre-mRNAs, and inactivation of U1-70K in yeast (Saccharomyces cerevisiae) is not lethal.

Function and glycosylation of plant-derived antiviral monoclonal antibody.

Plant genetic engineering led to the production of plant-derived mAb (mAbP), which provides a safe and economically feasible alternative to the current methods of antibody production in animal systems. In this study, the heavy and light chains of human anti-rabies mAb were expressed and assembled in planta under the control of two strong constitutive promoters. An alfalfa mosaic virus untranslated leader sequence and Lys-Asp-Glu-Leu (KDEL) endoplasmic reticulum retention signal were linked at the N and C terminus of the heavy chain, respectively.

Isolation and characterization of a novel calmodulin-binding protein from potato.

Tuberization in potato is controlled by hormonal and environmental signals. Ca(2+), an important intracellular messenger, and calmodulin (CaM), one of the primary Ca(2+) sensors, have been implicated in controlling diverse cellular processes in plants including tuberization. The regulation of cellular processes by CaM involves its interaction with other proteins.