Late embryogenesis abundant (LEA) proteins are well associated with the desiccation tolerance in organisms. LEA proteins are categorized into at least seven groups by virtue of similarities in their deduced amino acid sequences. Most of the LEA proteins have the characteristics of high hydrophilicity and thermo-stability. The LEA proteins are in unstructured conformation in aqueous solution. However, they adopted amphiphilic alpha-helix structure during desiccation condition. LEA proteins are localized to the different organelles in the cells, i.e. cytoplasm, endoplasmic reticulum, mitochondria and nucleus. The multi-functional capacity of LEA proteins are suggested, as protein stabilization, protection of enzyme activity, membrane association and stabilization, antioxidant function, metal-ion binding or DNA protection, etc. Here, we review the structural and functional characteristics of LEA proteins to provide a reference platform to understand their protective mechanisms during the adaptive response to desiccation in organisms.
Adaptation, Physiological ; Dehydration ; Desiccation ; Droughts ; Plant Physiological Phenomena ; Plant Proteins ; physiology ; Stress, Physiological

Botany ; history ; China ; History, 20th Century ; Plant Physiological Phenomena ; Universities

Secondary metabolites are the result of that plant interaction with biological and non-biological factors in the long-term evolution process, and play an important role in plant growth, development and physiology. The effective components of medicinal plant are usually the secondary metabolites in plant cells, and the synthesis of them are affected by a variety of factors, such as environmental impact. Acquirement of the secondary metabolites via callus culture has the advantage of low cost and less environmental impact. The synthesis and accumulation of medicinal plant secondary metabolites are not only controlled by light, temperature and pH, but also infected by germplasm, plant growth regulator and elicitor. This article presents a review of the influencing factors, and provides a basis for further study and development.
Light ; Plant Growth Regulators ; metabolism ; Plant Physiological Phenomena ; radiation effects ; Plants ; metabolism ; radiation effects ; Temperature

Polyamine is an important physiological regulation substance functioning in a wide variety of biological processes, such as plant growth, development, senescence and adversity stress tolerance, which widely exist in all living organisms. Their biosynthetic pathways have already been revealed, and their physiological roles are being elucidated gradually. Previous work on polyamines biosynthetic deficiency mutants and various transgenic plants facilitates improved understanding of the important roles of polyamines and biosynthetic enzymes in plant growth and development. This paper summarizes researches in the biosynthetic pathways of polyamines in plants, focusing on research advances on functions of genes involved in polyamine metabolism. In addition, the potential research directions, especially the application of the genes in the genetic engineering of plant stress tolerance were also discussed.
Biosynthetic Pathways ; physiology ; Gene Expression Regulation, Plant ; Genes, Plant ; genetics ; Plant Physiological Phenomena ; Plants ; metabolism ; Plants, Genetically Modified ; Polyamines ; metabolism ; Stress, Physiological

In this study, endophytic bacteria were isolated from roots of P. ginseng by plate culture method, and as a result, 40 endophytic bacterial strains were isolated, Bacillus spp. and Pseudomonas spp. were predominant. By confront culture method, two antagonistic endophytic bacterial strain, ge15 (Stenotrophomonas maltophilia) and ge25 (Bacillus sp. ) against Cylindrocarpon destructans, Sclerotinia schinseng and Alternaria pana were identified. The inhibition zone of ge15 to them were 5.5, 22.0, 14.8 mm, respectively; and which were 12.7,16.5,9.0 mm for ge25. The Results indicate that endophytic bacteria have biocontrol potential on ginseng pathogens, and which can be used as a bio-control factor on ginseng soilborne diseases control.
Bacteria ; isolation & purification ; Bacterial Physiological Phenomena ; Endophytes ; isolation & purification ; physiology ; Panax ; microbiology ; Plant Roots ; microbiology

Biological Science Disciplines ; history ; China ; History, 20th Century ; Humans ; Plant Physiological Phenomena

Aluminium (Al) toxicity is one of the major limiting factors for barley production on acid soils. It inhibits root cell division and elongation, thus reducing water and nutrient uptake, consequently resulting in poor plant growth and yield. Plants tolerate Al either through external resistance mechanisms, by which Al is excluded from plant tissues or internal tolerance mechanisms, conferring the ability of plants to tolerate Al ion in the plant symplasm where Al that has permeated the plasmalemma is sequestered or converted into an innocuous form. Barley is considered to be most sensitive to Al toxicity among cereal species. Al tolerance in barley has been assessed by several methods, such as nutrient solution culture, soil bioassay and field screening. Genetic and molecular mapping research has shown that Al tolerance in barley is controlled by a single locus which is located on chromosome 4H. Molecular markers linked with Al tolerance loci have been identified and validated in a range of diverse populations. This paper reviews the (1) screening methods for evaluating Al tolerance, (2) genetics and (3) mechanisms underlying Al tolerance in barley.
Aluminum ; metabolism ; toxicity ; Biological Assay ; Cell Wall ; metabolism ; Chromosomes, Plant ; Genes, Plant ; Genotype ; Hordeum ; metabolism ; Hydrogen-Ion Concentration ; Models, Genetic ; Plant Physiological Phenomena ; Soil ; Temperature

OBJECTIVETo evaluate the effects of infant formula containing palm oil on the nutrient absorption and defecation in infants.

METHODSA search in Cochrane Library, PubMed, OVID, Springer, China National Knowledge Infrastructure, Vip Chinese Periodical Database, Wanfang Chinese Periodical Database and Chinese Bio-medicine Database was performed to identify relevant English and Chinese language articles between January 1990 and March 2009. Two reviewers independently performed data extraction and appraised using Jadad instrument. Double data were input and analyzed by software of Review Manager 4.2 recommended by Cochrane Collaboration. Intestinal nutrient absorption, electrolyte content of fecal excretion, in vivo calcium deposition, and defecation were included as the target outcomes. These outcomes were evaluated as the combined standardized mean difference (SMD) and relative risk (RR) value and 95% CI of them.

RESULTSThirteen articles were included. Three articles meeting inclusion criteria were analyzed for the effects between infant formula containing palmitic acid at the Sn-2 positions and palmitic acid at the Sn-1, 3 positions; five articles were analyzed for the effects between infant formula containing palmitic acid at the Sn-1, 3 and without palmitic acid; another five articles were analyzed for the effects between infant formula containing palmitic acid at the Sn-2 positions and without palmitic acid. Absorption of fat and calcium was higher, the Ca(2+) of fecal excretion was lower when the infant formula provided palmitic acid at the Sn-2 positions or without palmitic acid than that determined when formula containing palmitic acid at the Sn-1 and Sn-3 positions was given (P < 0.01). The bone mineral content (BMC) and bone mineral density (BMD) increased at 3, 6 months when the infant formula without palmitic acid as compared with using the formula containing palmitic acid at the Sn-1 and Sn-3 positions (P < 0.01). The formation of calcium soaps in stool was reduced, the BMC increased when the infant formula provided palmitic acid at the Sn-2 positions as compared with using the infant formula without palmitic acid (P < 0.01). The incidence of soft stools was higher, and the incidence of hard stools was lower when the infant formula provided palmitic acid at the Sn-2 positions or without palmitic acid than that when formula containing palmitic acid at the Sn-1 and Sn-3 positions was used (P < 0.01).

CONCLUSIONAbsorption of fat and calcium was lower, the Ca(2+) of fecal excretion was higher, the BMC was reduced, the incidence of hard stools increased when the infant formula provided the palmitic acid at the Sn-1 and Sn-3 positions as compared with using formula contained palmitic acid at the Sn-2 positions or without palmitic acid. However, this conclusion should be used cautiously because of the limited quality of studies included into the analysis.

Defecation ; Humans ; Infant ; Infant Formula ; chemistry ; Infant Nutritional Physiological Phenomena ; Intestinal Absorption ; Palm Oil ; Palmitic Acid ; Plant Oils

Nitric oxide (NO) is a short-lived gaseous free radical that predominantly functions as a messenger and effector molecule. It affects a variety of physiological processes, including programmed cell death (PCD) through cyclic guanosine monophosphate (cGMP)-dependent and - independent pathways. In this field, dominant discoveries are the diverse apoptosis networks in mammalian cells, which involve signals primarily via death receptors (extrinsic pathway) or the mitochondria (intrinsic pathway) that recruit caspases as effector molecules. In plants, PCD shares some similarities with animal cells, but NO is involved in PCD induction via interacting with pathways of phytohormones. NO has both promoting and suppressing effects on cell death, depending on a variety of factors, such as cell type, cellular redox status, and the flux and dose of local NO. In this article, we focus on how NO regulates the apoptotic signal cascade through protein S-nitrosylation and review the recent progress on mechanisms of PCD in both mammalian and plant cells.
Animals ; Apoptosis ; physiology ; Caspases ; metabolism ; Caspases, Effector ; metabolism ; Cyclic GMP ; metabolism ; Mitochondria ; metabolism ; physiology ; Nitric Oxide ; metabolism ; physiology ; Plant Cells ; Plant Physiological Phenomena ; Signal Transduction ; physiology

Conventional breeding for dual resistance of disease and pest of Musa cultivars remains a difficult endeavor, as the plant is polyploidic and high in sterility. Biotechnological techniques, eg., genetic engineering, in vitro mutation breeding, or protoplast fusion, may overcome the difficulties and improve the germplasm. Establishment of a stable embryogenic cell suspension (ECS) is a prerequisite for any of the biotechnological breeding methods. In this study an embryogenic cell suspension was established from immature male flower of Musa acuminata cv. Mas (AA), a popular commercial variety of banana in the South-East Asian region. After culture for 5-6 months on callus induction media, which consisted of MS salts, different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), 4.1 micromol/L biotin, 5.7 micromol/L indoleacetic acid (IAA), 5.4 micromol/L naphthaleneacetic acid (NAA), other vitamins, 87 mmol/L sucrose, and solidified with 7 g/L agarose, meristematic globules and yellow, friable embryogenic cultures were induced from the explants of 1-15th row young floral hands of immature male flowers. Of the four treatments of 2,4-D, 9 micromol/L was the most effective on the callus induction, it transformed 40.96% and 7.45% of the cultivated male floral hands into callus and embryogenic callus respectively. The explants to produce highest frequency of the embryogenic calli were floral hands of 6 to 12th rows, which generated 5.79% of the embryogenic calli. Suspension cultures were initiated from these embryogenic calli in liquid medium supplemented with 4.5 micromol/L 2, 4-D. After sieving selection of the cultures using a stainless steel metallic strainer with pore sizes of 154 microm at 15 day intervals for 3 months, homogeneous and yellow embryogenic cell suspensions, composed of single cells and small cell aggregates, were established. Based upon the growth quantity and growth rate of ECS, it was determined that the appropriate inoculum was 2.0 mL PCV ECS/30 mL medium in 100 mL flask, and the appropriate subculture cycle was 15 days. Planting of 6 months old ECS on semi-solid medium of somatic embryo induction and development (MSD) resulted in approximately 280 x 10(3) somatic embryos/mL PCV ECS. MSD contained SH macronutrients, micro-nutrients, Fe-EDTA and MS vitamins supplemented with 4.5 micromol/L biotin, 680 micromol/L glutamine, 2 mmol/L proline, 100 mg/L malt extract, 1.1 micromol/L NAA, 0.2 micromol/L zeatin, 0.5 micromol/L kinetin, 0.7 micromol/L N6-(2-isopentenyl) adenine, 29 mmol/L lactose, 130 mmol/L sucrose and solidified with 2g/L gelrite. After 3 months of maturity on MSD, 17.28% of the somatic embryos were germinated on germination media (MG), consisted of MS salt, Morel and Wetmore vitamins, 0.2 micromol/L 6-BA, 1.1 micromol/L IAA, 87 micromol/L sucrose and solidified with 2 g/L gelrite; and 14.16% of the somatic embryos could develop into normal plantlets on rooting media contained the same composition as that of MG but without auxin and cytokinin.
2,4-Dichlorophenoxyacetic Acid ; pharmacology ; Culture Media ; Flowers ; drug effects ; embryology ; physiology ; Musa ; drug effects ; embryology ; physiology ; Plant Physiological Phenomena ; Regeneration ; Tissue Culture Techniques ; methods