Functional analysis of the seven in absentia ubiquitin ligase family in tomato

Seven in absentia (SINA) protein is one subgroup of ubiquitin ligases possessing an N‐terminal cysteine‐rich really interesting new gene (RING) domain, two zinc‐finger motifs, and a C‐terminal domain responsible for substrate‐binding and dimerization. In tomato (Solanum lycopersicum), the SINA gene family has six members, and we characterize in this study all tomato SINA (SlSINA) genes and the gene products. Our results show that SlSINA genes are differentially regulated in leaf, bud, stem, flower, and root. All SlSINA proteins possess RING‐dependent E3 ubiquitin ligase activity, exhibiting similar specificity towards the E2 ubiquitin‐conjugating enzyme. SlSINA1/3/4/5/6 are localized in both cytoplasm and nucleus, whereas SlSINA2 is exclusively localized in the nucleus. Moreover, all SlSINAs can interact with each other for homo‐ or hetero‐dimerization. The functionality of SlSINA proteins has been investigated. SlSINA4 plays a positive role in defense signalling, as manifested by elicitation of E3‐dependent hypersensitive response‐like cell death; the other SlSINAs are negative regulator and capable to suppress hypersensitive response cell death. Transgenic tomato plants overexpressing SlSINA2 exhibit pale‐green leaf phenotype, suggesting SlSINA2 regulates chlorophyll level in plant cells, whereas transgenic tomato plants overexpressing SlSINA5 have altered floral structure with exserted stigma, implicating SlSINA5 plays a role in flower development.     

Sugar complexation with calcium ion. Crystal structure and FT-IR study of a hydrated calcium chloride complex of D-ribose

The single crystal structure of CaCl(2).C(5)H(10)O(5).3H(2)O was determined with M(r)=315.16, a=7.537(3), b=11.426(5), c=15.309(6) A, beta=90 degrees, V=1318.3(9) A(3), P2(1)2(1)2(1), Z=2, mu=0.71073 A and R=0.0398 for 2322 observed reflections. The ribose moiety of the complex exists as a furanose with alpha-D configuration. All five oxygen atoms of the ribose molecule are involved in calcium binding. Each calcium ion is shared by two such sugar molecules, coordinating through O(1), O(2), O(3) of one molecule and O(4) and O(5) of the other. The C-C, O-H, C-O and C-O-H vibrations are shifted and the relative intensities changed in the complex IR spectrum, corresponding to the changes in bond distances and angles of the sugar structure. All the hydroxyl groups, water molecules and chloride ions are involved in forming an extensive hydrogen-bond network of O-H...Cl...O-H structure, and the chloride ions play an important role in the crystal packing.     

Molecular cloning and expression analysis of major intrinsic protein gene in Chlamydomonas sp. ICE-L from Antarctica

Extremophiles - Major intrinsic proteins (MIPs) form channels facilitating the passive transport of water and other small polar molecules across membranes. In this study, the complete open reading...     

Human adrenomedullin combined with human adrenomedullin binding protein-1 is protective in gut ischemia and reperfusion injury in the rat

Previous studies have demonstrated that co-administration of rat adrenomedullin (AM) and human AM binding protein-1 (AMBP-1) has various beneficial effects following adverse circulatory conditions. In order to reduce rat proteins to elicit possible immune responses in humans, we determined the effect of human AM combined with human AMBP-1 after intestinal ischemia and reperfusion (I/R). Intestinal ischemia was induced in the rat by occluding the superior mesenteric artery for 90 min. At 60 min after the beginning of reperfusion, human AM/AMBP-1 at 3 different dosages was administered intravenously over 30 min. At 240 min after the treatment, blood and tissue samples were harvested and measured for pro-inflammatory cytokines (i.e., TNF-alpha and IL-6), myeloperoxidase activities in the gut and lungs, and cleaved caspase-3 expression in the lungs, as well as serum levels of hepatic enzymes and lactate. In additional groups of animals, a 10-day survival study was conducted. Results showed that administration of human AM/AMBP-1 reduced pro-inflammatory cytokines, attenuated organ injury, and improved the survival rate in a seemingly dose-response fashion. Co-administration of the highest dose of human AM/AMBP-1 in this study had the optimal therapeutic effect in the rat model of intestinal I/R.     

Regulation of TB Vaccine-Induced Airway Luminal T Cells by Respiratory Exposure to Endotoxin

Tuberculosis (TB) vaccine-induced airway luminal T cells (ALT) have recently been shown to be critical to host defense against pulmonary TB. However, the mechanisms that maintain memory ALT remain poorly understood. In particular, whether respiratory mucosal exposure to environmental agents such as endotoxin may regulate the size of vaccine-induced ALT population is still unclear. Using a murine model of respiratory genetic TB vaccination and respiratory LPS exposure, we have addressed this issue in the current study. We have found that single or repeated LPS exposure increases the number of antigen-specific ALT which are capable of robust secondary responses to pulmonary mycobacterial challenge. To investigate the potential mechanisms by which LPS exposure modulates the ALT population, we have examined the role of ALT proliferation and peripheral T cell recruitment. We have found that LPS exposure-increased ALT is not dependent on increased ALT proliferation as respiratory LPS exposure does not significantly increase the rate of proliferation of ALT. But rather, we find it to be dependent upon the recruitment of peripheral T cells into the airway lumen as blockade of peripheral T cell supplies markedly reduces the initially increased ALT. Thus, our data suggest that environmental exposure to airborne agents such as endotoxin has a profound modulatory effect on TB vaccine-elicited T cells within the respiratory tract. Our study provides a new, M.tb antigen-independent mechanism by which the respiratory mucosal anti-TB memory T cells may be maintained.     

Unconditional and conditional QTL mapping for the developmental behavior of tiller number in rice (<Emphasis Type=Italic>Oryza sativa</Emphasis> L.)

A single segment substitution population of 26 lines and their recipient parent Hua-jing-xian 74 (HJX74) were selected as experimental materials for analyzing the developmental behavior of tiller number in rice. By the unconditional QTL (quantitative trait locus) mapping method, a total number of 14 SSSLs were detected with QTLs controlling rice tiller number. The number of QTLs significantly affecting tiller number and their effect values estimated differed across measuring stages. More QTLs could be detected based on time-dependent measures of different stages. By the conditional QTL mapping method, it is possible to reveal net expression of gene in a time interval. 14 QTLs on tiller number expressed their effects in dynamic patterns of themselves during whole ontogeny. They exhibited mainly negative effects within 7 days after transplanting. During 7–21 days, QTLs were in active status and expressed larger positive effects. In the mid-period of 21–35 days, they had opposite genetic effects to wither tillers. Since then these QTLs expressed positive effects again to cause the appearance of noneffective tillers. The dynamics of QTL effects was in agreement with the actual change of tillers. Mapping QTL combining unconditional with conditional analysis for time-dependent measures is helpful to understand roundly the genetic bases for the development of quantitative traits.