Identification of the isoamylase 3 gene in common wheat and its expression profile during the grain-filling period.

In higher plants, isoamylase-type starch debranching enzyme catalyzes the α-1,6-glucosidic linkages of glycogen and phytoglycogen. We cloned an isoamylase-type starch debranching enzyme ISA3 cDNA sequence (2883 bp), designated as TaISA3, from common wheat (Triticum aestivum), using the rapid amplification of cDNA ends method. The open reading frame of TaISA3 was found to have 2331 bp, and its deduced amino acid sequence was found to share high similarity with those of other gramineous plant ISA3 proteins. It contains a putative transit peptide (68 amino acids), N-terminus domain (107 amino acids), and a catalytic domain (173 amino acids). We extracted the expressed TaISA3 protein from Escherichia coli (BL21), and measured starch isoamylase activity. During the wheat grain-filling period, transcripts of the TaISA3 gene reached a maximum level at the early developmental stage, then declined, and increased again near the final maturation stage of the grain. We confirm that the ISA3 gene is present in common wheat; it appears to play a role in starch synthesis during early and late stages of the grain-filling period.

[Epidemiological characteristics and the development of spatiotemporal analysis models on hemorrhagic fever with renal syndrome in China].

Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease of natural infectious focus caused by Hantavirus (HV) with clinical characteristics as fever, hemorrhage, hyperemia, hypotensive shock and renal damage. Through contacting the excreta or secretion of infected rats, human may get infected. The epidemiological characteristics of HFRS are significantly different in terms of population differences, geographical heterogeneity and seasonal variation, which are all closely related to the habitat of host animals and human productive activities. The reported number of HFRS is about 150 000 to 200 000 each year worldwide, and China accounted for 70%-90% of the total reported cases standing the most seriously infected country. In this study, we reviewed the epidemiological characteristics and the influencing factors of HFRS as well as the models and methods used in relevant ecological studies, in order to understand the distribution of time, regional and population and potential influencing factors on the transmission of HFRS better, so as to improve the strategies on investigation, monitoring, prevention and control of the diseases.

Distribution of EP4 receptor in different Atlantic salmon (Salmo salar L.) tissues.

Prostaglandin E2 (PGE2) is an important lipid mediator that plays diverse functions in mammals. Four receptor subtypes of PGE2, designated EP1-4, have been identified to mediate its signaling pathways. Extensive studies of PGE2 and its receptors have been carried out in mammals, but little is known in fish, including Atlantic salmon. In the current study, the distribution of Atlantic salmon EP4 receptor in different tissues was investigated using RT- and real-time PCR. A custom made antibody was used to investigate the distribution of this receptor in different tissues. Quantitative analysis by real-time PCR revealed that the expression was more abundant in the spleen followed by head kidney, skin and fin while it was least expressed in heart, muscles and brain. The staining intensity obtained by immunohistochemistry correlated with the RT-PCR results. EP4 expression was strongly associated with the immune cells in different tissues. To our knowledge, this is the first study to describe the distribution of EP4 receptor in Atlantic salmon tissues. Our findings suggest that EP4 may play a role in mediating immune responses as observed in mammals.