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We report the synthesis and characterization of a series of novel mesogen‐jacketed liquid‐crystalline polymers, poly[2,5‐bis(4′‐alkoxycarbonylphenyl)styrene]s (1‐m, where m is the number of carbon atoms in the alkyl tails), along with the corresponding monomers, 2,5‐bis(4′‐alkoxycarbonylphenyl)styrenes (2‐m), and their precursors, 2,5‐bis(4′‐alkoxycarbonylphenyl)toluenes (3‐m). The influence of the tail length on the thermotropic properties of the two types of low‐molecular‐mass compounds and macromolecules was investigated with a combination of differential scanning calorimetry, polarized optical microscopy, and wide‐angle X‐ray diffraction techniques. Except for compound 3‐3, which exhibited a monotropic nematic phase, all members of the low‐molar‐mass molecules developed no mesophase during both heating and cooling processes. The glass‐transition temperatures of the polymers decreased as the tail lengths increased. The 5% weight loss temperatures of all the polymers under a nitrogen atmosphere were above 360 °C, indicating quite high thermal stability. Although polymers 1‐1 and 1‐2 were non‐liquid‐crystalline, columnar nematic phases were observed for the remaining homopolymers with longer alkyl tails. The mesophases of 1‐3 to 1‐9 that developed at high temperatures remained upon cooling to room temperature, whereas those of 1‐10 to 1‐12 disappeared during the cooling process. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 830–847, 2007. [ABSTRACT FROM AUTHOR]

MADS-domain proteins are important transcription factors involved in many biological processes of plants. In our study, a tomato MADS-box gene, SlFYFL, was isolated. SlFYFL is expressed in all tissues of tomato and significantly higher in mature leave, fruit of different stages, AZ (abscission zone) and sepal. Delayed leaf senescence and fruit ripening, increased storability and longer sepals were observed in 35S:FYFL tomato. The accumulation of carotenoid was reduced, and ethylene content, ethylene biosynthetic and responsive genes were down-regulated in 35S:FYFL fruits. Abscission zone (AZ) did not form normally and abscission zone development related genes were declined in AZs of 35S:FYFL plants. Yeast two-hybrid assay revealed that SlFYFL protein could interact with SlMADS-RIN, SlMADS1 and SlJOINTLESS, respectively. These results suggest that overexpression of SlFYFL regulate fruit ripening and development of AZ via interactions with the ripening and abscission zone-related MADS box proteins. [ABSTRACT FROM AUTHOR]

MADS-domain proteins are important transcription factors involved in many biological processes of plants. In our study, a tomato MADS-box gene, SlFYFL, was isolated. SlFYFL is expressed in all tissues of tomato and significantly higher in mature leave, fruit of different stages, AZ (abscission zone) and sepal. Delayed leaf senescence and fruit ripening, increased storability and longer sepals were observed in 35S:FYFL tomato. The accumulation of carotenoid was reduced, and ethylene content, ethylene biosynthetic and responsive genes were down-regulated in 35S:FYFL fruits. Abscission zone (AZ) did not form normally and abscission zone development related genes were declined in AZs of 35S:FYFL plants. Yeast two-hybrid assay revealed that SlFYFL protein could interact with SlMADS-RIN, SlMADS1 and SlJOINTLESS, respectively. These results suggest that overexpression of SlFYFL regulate fruit ripening and development of AZ via interactions with the ripening and abscission zone-related MADS box proteins. [ABSTRACT FROM AUTHOR]

The synthesis and chiroptical properties of two novel optically active helical glycopolymers, poly{2,5-bis[4′-(2,3,4,6-tetra- O-acetyl-beta- d-galactosyloxy)phenyl]styrene} (PTAGPS) and poly{2,5-bis[4′-(β- d-galactosyloxy)phenyl]styrene} (PGPS), were reported. The former was obtained via radical polymerization of 2,5-bis[4′-(2,3,4,6-tetra- O-acetyl-β- d-galactosyloxy)phenyl]styrene (TAGPS), while the later by either direct radical polymerization of deacetylized monomer, 2,5-bis[4′-(β- d-galactosyloxy)phenyl]styrene (GPS), or deacetylation of PTAGPS. PTAGPS had a thermodynamically controlled conformation (TCC) regardless of the nature of the solvent where it was polymerized. However, PGPS prepared via radical polymerization of GPS in dimethyl sulfoxide (DMSO) had TCC, and that in N, N-dimethylformamide (DMF) had a kinetically controlled conformation (KCC), which could undergo an irreversible evolution to TCC by annealing in DMSO. PGPS derived from PTAGPS showed the essential chiroptical characteristics of both its precursor and PGPS with KCC obtained in DMF. These results demonstrated that achiral acetyl groups in the monomer molecule had a remarkable effect on the formation of chiral secondary structure of the polymer. [ABSTRACT FROM AUTHOR]