The pattern of protein synthesis changes rapidly and dramatically when the growth temperature of soybean seedling tissue is increased from 280C (normal) to about 400C (heat shock). The synthesis of normal proteins is greatly decreased and a new set of proteins, "heat shock proteins," is induced. The'heat shock proteins of soybean consist of 10 new bands on one-dimensional NaDodSO4 gels; a more complex pattern is observed on two-dimensional gels. When the tissue is returned to. 28!C after 4 hr at 40°C, there is progressive decline in the synthesis of heat shock proteins and reappearance of a normal pattern of-synthesis by 3 or 4 hr. In vitro translation of poly(A)+RNAs isolated from tissues grown at 28 and 400C shows that the heat shock proteins are translated from a new set of mRNAs induced at 400C; furthermore, the abundant class mRNAs for many of the normal proteins persist even though they -are translated weakly (or not;at all) in vivo at40 or 42.5 YC. The heat shock response in soybean appears similar to'the much studied heat shock phenomenon in Drosophila.Protein synthesis responds rapidly and dramatically to stress in a wide range of organisms. In soybean seedlings exposed to anaerobic conditions or incubation in dinitrophenol there is a fast read-out of polyribosomes which results--in a rapid transition from polyribosomes to mostly monoribosomes and a new low rate of protein synthesis (1). Water stress in maize seedlings similarly leads to a rapid loss of polyribosomes and low levels' of protein synthesis (e.g., refs. 2 and 3). In the case of anaerobiosis, much of the pre-stress mRNA persists for several hours during the anaerobic treatment in both soybean (1) and maize (4). In the case of maize roots, at least, the anaerobic treatment also results in the synthesis of a small number of new mRNAs and proteins and, as noted above, a greatly decreased' (or no) level of translation of the pre-stress mRNAs (4,5).These results together with those relating.to the much-stud. ied heat shock phenomenon of.Drosophila (see ref. 6) suggest that these changes in the patterns of mRNA and protein synthesis result from the induction by the stress agentof some regulatory event(s). In Drosophila (6) and a number of other systems studied to date (e.g., refs. 7-10) a change from the normal growth temperature to an increased temperature (e.g.,. 250C to 370C in the case of Drosophila) results in the shut-off (or reduction) of normal protein synthesis in concert with the induction of a set of "heat shock proteins." The heat shock response seems to be representative of a more general stress response because a wide range of stress agents induce the heat shock proteins in Drosophila (6) and a set of similar proteins in other systems (e.g., refs. 7 and 9).Except for the alcohol dehydrogenases induced by anaerobiosis in maize (4), the identity of the stress proteins remains obscure. There is some progress, however, in localizing at the subeellular level some of the heat shock proteins in Drosophila (e.g., refs. 11 and 12).We...

When soybean Glycine max var Wayne seedlings are shifted from a normal growth temperature of 28°C up to 40°C (heat shock or HS), there is a dramatic change in protein synthesis. A new set of proteins known as heat shock proteins (HSPs) is produced and normal protein synthesis is greatly reduced. A brief 10-minute exposure to 45°C followed by incubation at 28°C also results in the synthesis of HSPs. Prolonged incubation (e.g. 1-2 hours) at 45°C results in greatly impaired protein synthesis and seedling death. However, a pretreatment at 40°C or a brief (10-minute) pulse treatment at 45°C followed by a 28C incubation provide protection (thermal tolerance) to a subsequent exposure at 45C. Maximum thermoprotection is achieved by a 2-hour 40°C pretreatment or after 2 hours at 28C with a prior 10-minute 45°C exposure. Arsenite treatment (50 micromolar for 3 hours) also induces the synthesis of HSPlike proteins, and also provides thermoprotection to a 45C HS; thus, there is a strong positive correlation between the accumulation of HSPs and the acquisition of thermal tolerance under a range of conditions. During 40°C HS, some HSPs become localized and stably associated with purified organelle fractions (cg. nuclei, mitochondria4 and ribosomes) while others do not. A chase at 28C results in the gradual loss over a 4-hour period of the HSPs from the organelle fractions, but the HSPs remain selectively localized during a 40C chase period. If the seedlings are subjected to a second HS after a 28C chase, the HSPs rapidly (complete within 15 minute) relocalize in the organelle fractions.The relative amount of the HSPs which relocalize during a second HS increases with higher temperatures from 40°C to 45C. Proteins induced by arsenite treatment are not selectively localized with organelle fractions at 28C but become orpnelle-associated during a subsequent HS at 40°C.The induction of HSPs3 has been shown to be a universal response to thermal stress in a wide range of organisms (5-7, 9, 15, 21, 24, 30, 34 In this report, we present three lines of evidence supporting the role of HSPs in the acquisition of thermotolerance in plants. The criteria for thermoprotection are based on both the growth of soybean seedlings after a 2-h treatment at the lethal temperature of 45°C and the level of amino acid incorporation at this temperature. First, evidence is presented that the two conditions which stimulate the production of HSPs, i.e. a brief exposure to 45°C followed by incubation at 28°C or a somewhat longer exposure to 40°C, provide thermoprotection. Second, some HSPs become selectively localized in cellular organelles during HS and relocalize during a second heat shock after delocalization by a chase at 28°C. A third line of evidence is based on the induction by arsenite of HSP-like proteins. In soybean (results ofthis study) and other systems (5, 14), this respiratory inhibitor stimulates the production of electrophoretically similar proteins that provide thermoprotection and which become localized only during HS in the soyb...

Human papillomavirus (HPV), a small, nonenveloped, double-stranded DNA virus, is established as the key etiological factor in cervical neoplasms (24,29,30). More than 90% of cervical neoplasms are attributed to HPV infection. Persistence of high-risk HPV types is a major risk factor for the development of high-risk cervical intraepithelial neoplasia (CIN) (9). Although the regression of HPV infection commonly takes place within 3 years, compelling evidence indicated that a small but definite fraction of the infected population is at risk for developing invasive cervical cancer after many years or decades of a long latency period of primary infection (3,10,14).Currently, HPV DNA testing has played a triage role for atypical squamous cells of undetermined significance (ASCUS), primary screening in conjunction with cytology for the detection of cervical cancer and CIN, and follow-up in a variety of clinical settings (4,15,16,18,25).HPV DNA detection by the FDA-approved Hybrid Capture II HPV DNA test (HCII) (Digene Corporation, Gaithersburg, MD) is the most widely used method. The HCII system, a commercial liquid hybridization kit using RNA probes against HPV DNA genomic targets followed by signal amplification, has been validated for its reproducibility in HPV DNA detection (18,26,29). Thirteen carcinogenic types implicated in the pathogenesis of high-grade squamous intraepithelial lesions (HSILs) and invasive cancer, such as HPV type 16 (HPV

A cDNA encoding a small cysteine-rich protein designated VrCRP was isolated from a bruchid-resistant mungbean. VrCRP encodes a protein of 73 amino acids containing a 27 amino acid signal peptide and 8 cysteines. On the basis of the amino acid sequence similarity and conserved residues, it is suggested that VrCRP is a member of the plant defensin family. VrCRP protein was obtained by overexpression of VrCRP with a truncated signal peptide in an IMPACT system. Artificial seeds containing 0.2% (w/w) of the purified VrCRP-TSP were lethal to larvae of the bruchid Callosobruchus chinensis. VrCRP is apparently the first reported plant defensin exhibiting in vitro insecticidal activity against C. chinensis.

Imbalanced splicing of premessenger RNA is typical of tumorous malignancies, and the regulatory mechanisms involved in several tumorigenesis-associated splicing events are identified. Elevated expression of serine-arginine protein kinase 1 (SRPK1) may participate in the pathway responsible for the dysregulation of splicing events in malignant tumor cells. In this study, we observed a correlation between the cytoplasmic accumulation of RNA-binding motif protein 4 (RBM4) and up-regulated SRPK1 in breast cancer cells. The production of the IR-B and MCL-1 S transcripts was induced separately by the overexpression of RBM4 and SRPK1 gene silencing. Overexpressed RBM4 simultaneously bound to the CU-rich elements within the MCL-1 exon2 and the downstream intron, which subsequently facilitated the exclusion of the regulated exon. Breast cancer cells are deprived of apoptotic resistance through the RBM4-mediated up-regulation of the IR-B and MCL-1 S transcripts. These findings suggest that the splicing events regulated by the SRPK1-RMB4 network may contribute to tumorigenesis through altered sensitivity to apoptotic signals in breast cancer cells.

BackgroundDespite of the trend that the application of DNA methylation as a biomarker for cancer detection is promising, clinically applicable genes are few. Therefore, we looked for novel hypermethylated genes for cervical cancer screening.Methods and FindingsAt the discovery phase, we analyzed the methylation profiles of human cervical carcinomas and normal cervixes by methylated DNA immunoprecipitation coupled to promoter tiling arrays (MeDIP-on-chip). Methylation-specific PCR (MSP), quantitative MSP and bisulfite sequencing were used to verify the methylation status in cancer tissues and cervical scrapings from patients with different severities. Immunohistochemical staining of a cervical tissue microarray was used to confirm protein expression. We narrowed to three candidate genes: DBC1, PDE8B, and ZNF582; their methylation frequencies in tumors were 93%, 29%, and 100%, respectively. At the pre-validation phase, the methylation frequency of DBC1 and ZNF582 in cervical scraping correlated significantly with disease severity in an independent cohort (n = 330, both P<0.001). For the detection of cervical intraepithelial neoplasia 3 (CIN3) and worse, the area under the receiver operating characteristic curve (AUC) of ZNF582 was 0.82 (95% confidence interval  = 0.76–0.87).ConclusionsOur study shows ZNF582 is frequently methylated in CIN3 and worse lesions, and it is demonstrated as a potential biomarker for the molecular screening of cervical cancer.

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