The apoAI/CIII/AIV gene cluster is involved in lipid metabolism and has a complex pattern of gene expression modulated by a common regulatory element, the apoCIII enhancer. A new member of this cluster, apolipoprotein (apo) AV, has recently been discovered as a novel modifier in triglyceride metabolism. To determine the expression of all four apo genes in combination and, most importantly, whether the transcription of apoAV is coregulated by the apoCIII enhancer in the cluster, we generated an intact transgenic line carrying the 116-kb human apoAI/CIII/AIV/AV gene cluster and a mutant transgenic line in which the apoCIII enhancer was deleted from the 116-kb structure. We demonstrated that the apoCIII enhancer regulated hepatic and intestinal apoAI, apoCIII, and apoAIV expression; however, it did not direct the newly identified apoAV in the cluster. Furthermore, human apo genes displayed integrated position-independent expression and a closer approximation of copy number-dependent expression in the intact transgenic mice. Because apoCIII and apoAV play opposite roles in triglyceride homeostasis, we analyzed the lipid profiles in our transgenic mice to assess the effects of human apoAI gene cluster expression on lipid metabolism. The triglyceride level was elevated in intact transgenic mice but decreased in mutant ones compared with nontransgenic mice. In addition, the expression of human apoAI and apoAIV elevated high density lipoprotein cholesterol in transgenic mice fed an atherogenic diet. In conclusion, our studies with human apoAI/CIII/ AIV/AV gene cluster transgenic models showed that the apoCIII enhancer regulated expression of apoAI, apo-CIII, and apoAIV but not apoAV in vivo and showed the influences of expression of the entire cluster on lipid metabolism.The genes coding apoAI, apoCIII, and apoAIV are clustered within a 17-kb DNA segment on the long arm of human chromosome 11 (1). Comparative sequence analysis recently disclosed a new apolipoprotein (apo) 1 family member, apoAV, located about 30 kb proximal to the apoAI/CIII/AIV gene cluster (2) (Fig. 1). apoAI is the major protein component of HDL. apoAI levels correlate positively with HDL cholesterol and negatively with atherosclerotic cardiovascular diseases (3). Transgenic mice overexpressing human apoAI are protected from diet-related or apoE deficiency-related atherosclerotic lesions (4, 5). apoCIII is the major component of VLDL and a minor component of HDL, and mice carrying human apoCIII develop severe hypertriglyceridemia (6, 7). HDL is a major carrier of plasma apoAIV, and overexpression of human apoAIV decreases aortic lesions in transgenic mice (8, 9). apoAV is found mainly in HDL and VLDL, and human apoAV transgenic mice display ϳ30% triglyceride level compared with wild-type mice (2). In humans, several important single-nucleotide polymorphisms within the apoAI cluster genes have been shown to be strongly associated with dyslipidema and to increase susceptibility to atherosclerosis (10, 11). Recently, such research has focused on associa...

Laccase, as a copper-containing polyphenol oxidase, primarily functions in the process of lignin, anthocyanin biosynthesis, and various abiotic/biotic stresses. In this study, forty-eight laccase members were identified in the eggplant genome. Only forty-two laccase genes from eggplant (SmLACs) were anchored unevenly in 12 chromosomes, the other six SmLACs were mapped on unanchored scaffolds. Phylogenetic analysis indicated that only twenty-five SmLACs were divided into six different groups on the basis of groups reported in Arabidopsis. Gene structure analysis revealed that the number of exons ranged from one to 13. Motif analysis revealed that SmLACs included six conserved motifs. In aspects of gene duplication analysis, twenty-one SmLACs were collinear with LAC genes from Arabidopsis, tomato or rice. Cis-regulatory elements analysis indicated many SmLACs may be involved in eggplant morphogenesis, flavonoid biosynthesis, diverse stresses and growth/development processes. Expression analysis further confirmed that a few SmLACs may function in vegetative and reproductive organs at different developmental stages and also in response to one or multiple stresses. This study would help to further understand and enrich the physiological function of the SmLAC gene family in eggplant, and may provide high-quality genetic resources for eggplant genetics and breeding.

Stress-associated proteins (SAP), a class of zinc-finger proteins, have been identified as novel stress regulatory proteins in stress responses. However, SAP genes in eggplant (SmSAP) have been little reported. It has important significance in identifying SAP members, understanding the molecular mechanisms underlying stress responses, and tolerance. We performed a comprehensive study of the A20/AN1 domains, motifs, gene structures, phylogenetic relationships, chromosomal locations, gene replications, collinearity, cis-acting elements, and expression pattern responses to various abiotic stresses. Twenty-one SAP genes were identified in eggplant (SmSAP) and were localized on 10 chromosomes. A phylogenetic analysis revealed that most of the SmSAP proteins showed a high homology with the tomato SAP members, and 21 members were divided into four groups based on the homology of the SAP members in eggplant, tomato, rice, and Arabidopsis. Further analysis revealed that SmSAP proteins contain the characteristic A20/AN1 domains, the A20 domain composed of motif 2 (ILCINNCGFFGSPATMNLCSKCYKDMJLK). Four pairs of tandem duplications were found in eggplant, and 10 SmSAP genes had collinearity with SAP genes from Arabidopsis, potato, or tomato, but only four SmSAP genes were collinear with SAP genes in the three species mentioned above. Moreover, the promoters of SmSAP genes were predicted to contain many cis-acting elements that respond to abiotic stress and hormones. A qRT-PCR analysis of the four selected SmSAP genes exhibited diverse expression levels in response to various environmental stresses. These results provided a comprehensive analysis of the SmSAP genes and lay a solid foundation for improving the understanding of the functional diversification of SAP genes under various environmental stresses in eggplant.

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Sorbus sibirica fruits, popularly consumed as tea, is believed to promote healthy, relieve a cough. The literature reporting pharmacological studies related to Sorbus sibirica is very limited. Thus, The antioxidant activities of extracts from Sorbus sibirica fruits were evaluated using various in vitro assays including total flavonoid contents, total antioxidant activity, reducing power, lipid peroxidation inhibitory activity, scavenging hydroxyl and superoxide anion free radicals activity, and protective effects against DNA and protein damages. We selected the process of ultrasound-assisted extraction for total flavonoids from Sorbus sibirica fruits according to the extraction rate of total flavonoids. Results showed that the content of total flavonoids was 0.82 g per 100 g dry fruits sample obtained with ultrasound-assisted extraction method. The extracts exhibited strong scavenging capability with respect to hydroxyl and superoxide anion free radicals, and effectively inhibited the lipid peroxidation of polyunsaturated fatty acids. They also had good reducing power and protection against DNA and protein damage. Therefore, they might offer an important source of effective natural antioxidants in the food and cosmetic industries.