Characterization of three heat shock protein 70 genes from Liriomyza trifolii and expression during thermal stress and insect development.

Heat shock proteins (HSPs) participate in diverse physiological processes in insects, and HSP70 is one of the most highly conserved proteins in the HSP family. In this study, full-length cDNAs of three HSP70 genes (Lthsc70, Lthsp701, and Lthsp702) were cloned and characterized from Liriomyza trifolii, an important invasive pest of vegetable crops and horticultural crops worldwide. These three HSP70s exhibited signature sequences and motifs that are typical of the HSP70 family. The expression patterns of the three Lthsp70s during temperature stress and in different insect development stages were studied by real-time quantitative PCR. Lthsp701 was strongly induced by high- and low-temperature stress, but Lthsc70 and Lthsp702 were not very sensitive to temperature changes. All three Lthsp70s were expressed during insect development stages, but the expression patterns were quite different. The expression of Lthsc70 and Lthsp702 showed significant differences in expression during leafminer development; Lthsc70 was most highly expressed in female adults, whereas Lthsp702 was abundantly expressed in larvae and prepupae. Lthsp701 expression was not significantly different among leafminer stages. These results suggest that functional differentiation within the LtHSP70 subfamily has occurred in response to thermal stress and insect development.

Population genetic structure and migration patterns of Liriomyza sativae in China: moderate subdivision and no Bridgehead effect revealed by microsatellites.

While Liriomyza sativae (Diptera: Agromyzidae), an important invasive pest of ornamentals and vegetables has been found in China for the past two decades, few studies have focused on its genetics or route of invasive. In this study, we collected 288 L. sativae individuals across 12 provinces to explore its population genetic structure and migration patterns in China using seven microsatellites. We found relatively low levels of genetic diversity but moderate population genetic structure (0.05 < F ST < 0.15) in L. sativae from China. All populations deviated significantly from the Hardy-Weinberg equilibrium due to heterozygote deficiency. Molecular variance analysis revealed that more than 89% of variation was among samples within populations. A UPGMA dendrogram revealed that SH and GXNN populations formed one cluster separate from the other populations, which is in accordance with STRUCTURE and GENELAND analyses. A Mantel test indicated that genetic distance was not correlated to geographic distance (r = -0.0814, P = 0.7610), coupled with high levels of gene flow (M = 40.1-817.7), suggesting a possible anthropogenic influence on the spread of L. sativae in China and on the effect of hosts. The trend of asymmetrical gene flow was from southern to northern populations in general and did not exhibit a Bridgehead effect during the course of invasion, as can be seen by the low genetic diversity of southern populations.

[Diagnostic changes in serum creatine kinase MM isoenzyme sub-bands after the onset of acute myocardial infarction].

The authors quantified the change of CK-MM isoforms in the first available serum sample from 16 patients each with acute myocardial infarction (AMI) and angina pectoris and 16 normal individuals as well. The average MM3/MM1 ratio in the normal group was 0.24 +/- 0.12, in angina group 0.21 +/- 0.13, and in AMI group 0.52 +/- 0.30 (P less than 0.001, as compare with the first two groups). The first blood sample of AMI was obtained in 3.0 +/- 1.9 hours after the onset of chest pain. Half of them (8/16) had a ratio of MM3/MM1 greater than 0.50 and the change occurred as early as 30 min after the attack. In contrast, the total CK and CK-MB in the three groups were within normal limits at the same time, they were 85.8 +/- 24.4 U/L for CK and 3.2 +/- 1.1% for CK-MB in patients with AMI, 66.7 +/- 18.0 U/L, 2.7 +/- 1.6% in angina pectoris and 71.4 +/- 24.5 U/L, 3.0 +/- 1.1% in normal subjects respectively. Accordingly, diagnostic change of CK-MM isoforms was the earliest among the enzymes after the onset of AMI.