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T Wang

Publications and source records attributed to T Wang.

At least 55 records · Page 3Linked to original sources
PubMed2004

Alpha-adrenergic regulation of systemic peripheral resistance and blood flow distribution in the turtle Trachemys scripta during anoxic submergence at 5 degrees C and 21 degrees C.

Anoxic exposure in the anoxia-tolerant freshwater turtle is attended by substantial decreases in heart rate and blood flows, but systemic blood pressure (P(sys)) only decreases marginally due to an increase in systemic peripheral resistance (R(sys)). Here, we investigate the role of the alpha-adrenergic system in modulating R(sys) during anoxia at 5 degrees C and 21 degrees C in the turtle Trachemys scripta, and also describe how anoxia affects relative systemic blood flow distribution (%.Q(sys)) and absolute tissue blood flows. Turtles were instrumented with an arterial cannula for measurement of P(sys) and ultrasonic flow probes on major systemic blood vessels for determination of systemic cardiac output ((.Qsys)). Alpha-adrenergic tone was assessed from vascular injections of alpha-adrenergic agonists and antagonists (phenylephrine and phentolamine, respectively) during normoxia and following either 6 h (21 degrees C) or 12 days (5 degrees C) of anoxic submergence. Coloured microspheres, injected through a left atrial cannula during normoxia and anoxia, as well as after alpha-adrenergic stimulation and blockade during anoxia at both temperatures, were used to determine relative and absolute tissue blood flows. Anoxia was associated with an increased R(sys) and functional alpha-adrenergic vasoactivity at both acclimation temperatures. However, while anoxia at 21 degrees C was associated with a high systemic alpha-adrenergic tone, the progressive increase of R(sys) at 5 degrees C was not mediated by alpha-adrenergic control. A redistribution of blood flow away from ancillary vascular beds towards more vital circulations occurred with anoxia at both acclimation temperatures. %.Q(sys) and absolute blood flow were reduced to the digestive and urogenital tissues (approximately 2- to 15-fold), while %.Q(sys) and absolute blood flows to the heart and brain were maintained at normoxic levels. The importance of liver and muscle glycogen stores in fueling anaerobic metabolism were indicated by increases in %.Q(sys) to the muscle at 21 degrees C (1.3-fold) and liver at 5 degrees C (1.7-fold). As well, the crucial importance of the turtle shell as a buffer reserve during anoxic submergence was indicated by 40-50% of .Q(sys) being directed towards the shell during anoxia at both 5 degrees C and 21 degrees C. Alpha-adrenergic stimulation and blockade during anoxia caused few changes in %.Q(sys) and absolute tissue blood flow. However, there was evidence of alpha-adrenergic vasoactivity contributing to blood flow regulation to the liver and shell during anoxic submergence at 5 degrees C.

Adrenergic alpha-Agonists↗
PubMed2004

Limited extracellular but complete intracellular acid-base regulation during short-term environmental hypercapnia in the armoured catfish, Liposarcus pardalis.

Environmental hypercapnia induces a respiratory acidosis that is usually compensated within 24-96 h in freshwater fish. Water ionic composition has a large influence on both the rate and degree of pH recovery during hypercapnia. Waters of the Amazon are characteristically dilute in ions, which may have consequences for acid-base regulation during environmental hypercapnia in endemic fishes. The armoured catfish Liposarcus pardalis, from the Amazon, was exposed to a water P(CO(2)) of 7, 14 or 42 mmHg in soft water (in micromol l(-1): Na(+), 15, Cl(-), 16, K(+), 9, Ca(2+), 9, Mg(2+), 2). Blood pH fell within 2 h from a normocapnic value of 7.90+/-0.03 to 7.56+/-0.04, 7.34+/-0.05 and 6.99+/-0.02, respectively. Only minor extracellular pH (pH(e)) recovery was observed in the subsequent 24-96 h. Despite the pronounced extracellular acidosis, intracellular pH (pH(i)) of the heart, liver and white muscle was tightly regulated within 6 h (the earliest time at which these parameters were measured) via a rapid accumulation of intracellular HCO(3)(-). While most fish regulate pH(i) during exposure to environmental hypercapnia, the time course for this is usually similar to that for pH(e) regulation. The degree of extracellular acidosis tolerated by L. pardalis, and the ability to regulate pH(i) in the face of an extracellular acidosis, are the greatest reported to date in a teleost fish. The preferential regulation of pH(i) in the face of a largely uncompensated extracellular acidosis in L. pardalis is rare among vertebrates, and it is not known whether this is associated with the ability to air-breathe and tolerate aerial exposure, or living in water dilute in counter ions, or with other environmental or evolutionary selective pressures. The ubiquity of this strategy among Amazonian fishes and the mechanisms employed by L. pardalis are clearly worthy of further study.

Acid-Base Equilibrium↗
PubMed2004

Overview of surface ozone variability in East Asia-North Pacific region during IGAC/APARE (1994--1996).

Surface ozone (O3) was measured at Oki Island (Japan), Cheju Island (South Korea), Lanyu Island (Taiwan Province, China), Cape D'Aguilar (Hong Kong SAR) and Lin'an, Longfenshan, Waliguan (China mainland) during January 1994--December 1996 as a component of IGAC/APARE (International Global Atmospheric Chemistry/East Asia-North Pacific Regional Experiment). This paper gave a joint discussion on the observational results at these stations over the study region. Investigations showed that the average of surface O3 mixing ratios at the seven sites are 47.9+/-15.8, 48.1+/-17.9, 30.2+/-16.4, 31.6+/-17.5, 36.3+/-17.5, 34.8+/-11.5 and 48.2+/-9.5 ppbv, respectively. Significant diurnal variations of surface O3 have been observed at Oki, Cheju, D'Aguilar, Lin'an and Longfenshan. Their annual averaged diurnal differences range from 8 to 23 ppbv and differ in each season. Surface O3 at Lanyu and Waliguan do not show strong diurnal variability. Seasonal cycles of surface O3 showed difference at the temperate and the subtropical remote sites. Oki has a summer minimum-spring maximum, while Lanyu has a summer minimum-autumn maximum. The suburban sites at D'Aguilar and Lin'an report high-level O3 in autumn and low level O3 in summer. Surface O3 remains-high in autumn and low in winter at the rural site Longfenshan. For the global background station Waliguan, surface O3 exhibits a broad spring-summer maximum and autumn-winter minimum. The backward air trajectories to these sites have shown different pathways of long-range transport of air pollution from East Asia Continent to North Pacific Ocean. Surface O3 was found to be strongly and positively correlated with CO at Oki and Lanyu, especially in spring and autumn, reflecting the substantial photochemical buildup of O3 on a regional scale. It is believed that the regional sources of pollution in East Asia have enhanced the average surface O3 concentrations in the background atmosphere of North Pacific.

Air Movements↗
PubMed2003

Primary thoracolumbar scoliosis in pinealectomized chickens.

STUDY DESIGN: This study examines the gross anatomic changes in the chicken spine after pinealectomy and was undertaken because initial observation suggested that the pattern of curve development appears to be different from that reported in the literature. OBJECTIVE: To characterize the spinal deformity in chickens after pinealectomy. SUMMARY OF BACKGROUND DATA: The most common curve pattern seen after pinealectomy in chickens is said to be thoracic curves with structural changes and rotation. This is based largely on radiographic observations and forms the basis of the claim that chicken and human adolescent idiopathic scoliosis are similar. METHOD: Thirty-five chickens were divided into 2 groups, a pinealectomy group (n = 25) and a control group with no surgery performed (n = 10). The spines were harvested at 3 months of age and examined visually, by radiographs and computed tomography scans. RESULTS: Thirteen out of 25 (52%) of the pinealectomized chickens developed scoliosis. In contrast to previous studies, all the curves were located at the thoracolumbar junction with the apex at either T7 or L1. Structural changes including apical vertebral wedging, lordosis (mean of 14.3 degrees ), and rotation (mean of 14 degrees ) were seen in all cases. Pelvic wing deformity was seen in all cases and significantly contributed to the posterior rotational hump. CONCLUSION: The primary curve in these chickens is at the thoracolumbar junction. Previous reports of curve pattern based on radiographic findings would not have identified these as the thoracolumbar junction is obscured by the bony pelvis and heavy musculature. The finding of pelvic wing deformity has not been previously reported, and raises the question as to whether these curves are secondary to asymmetric muscle pull.

Animals↗
PubMed2003

Low frequency transmission of a plastid-encoded trait in Setaria italica.

It has been claimed that engineering traits into the chloroplast will prevent transgene transmission by pollen, precluding transgene flow from crops. A Setaria italica (foxtail or birdseed millet) with chloroplast-inherited atrazine resistance (bearing a nuclear dominant red-leaf base marker) was crossed with five male-sterile yellow- or green-leafed herbicide susceptible lines. Chloroplast-inherited resistance was consistently pollen transmitted at a 3x10(-4 )frequency in >780,000 hybrid offspring. The nuclear marker segregated in the F(2), but resistance did not segregate, as expected. Pollen transmission of plastome traits can only be detected using both large samples and selectable genetic markers. The risk of pollen transmission at this frequency would be several orders of magnitude greater than spontaneous nuclear-genome mutation-rates. Chloroplast transformation may be an unacceptable means of preventing transgene outflow, unless stacked with additional mechanisms such as mitigating genes and/or male sterility.

Cell Nucleus↗
PubMed2003

Effect of melatonin suppression on scoliosis development in chickens by either constant light or surgical pinealectomy.

STUDY DESIGN: This study was designed to compare the effect of suppression of melatonin secretion by bright light in chickens with that of surgical pinealectomy. OBJECTIVE: To determine whether suppression of melatonin secretion without surgery in chickens can result in scoliosis development. SUMMARY OF BACKGROUND DATA: Pinealectomy in chickens consistently produces scoliosis with anatomic characteristics similar to those of human idiopathic scoliosis. Conversely, cutting of the pineal stalk without removal of the pineal gland will also result in scoliosis. This study addresses the question of whether constant bright light can induce scoliosis formation, because it is well known that 24-hour bright lighting conditions can suppress the secretion of melatonin to an equivalent level as pinealectomy. MATERIALS AND METHOD: Seventy-seven newborn Nihon chickens were separated into three groups. A control group (n = 21) with no surgery performed; a pinealectomy group (n = 15) that served as surgical controls; and a constant light group (n = 41). The first two groups were kept together in a strict 12-hour light-dark cycle, whereas the third group was separately kept with constant lighting conditions (>100 lux). All the chickens were radiographed at two weekly intervals, and blood was taken during the middle of the light and dark cycles for serum melatonin assay using ELISA. RESULTS: Fifty-four percent of the pinealectomized chickens had scoliosis develop by 6 weeks. None of the constant-light chickens or controls had scoliosis develop for up to 11 weeks. Measurements of serum melatonin levels of the constant light group confirm that secretion is suppressed. CONCLUSION: This study suggests that for scoliosis to develop in chickens, the surgical operation itself is important and challenges the role of melatonin as an isolated etiological factor in the development of scoliosis.

Animals↗
PubMed2003

Distribution and regulation of expression of serum- and glucocorticoid-induced kinase-1 in the rat kidney.

The serum- and glucocorticoid-induced kinase-1 (sgk1) increases the activity of a number of epithelial ion channels and transporters. The present study examines the distribution and subcellular localization of sgk1 protein in the rat kidney and the regulation of levels of expression induced by steroids. The results indicate that the kidney expresses predominantly the sgk1 isoform with a distribution restricted to the thick ascending limb of Henle, distal convoluted, connecting and cortical collecting tubules. Within cells, sgk1 strongly associates with the microsomal fraction of homogenates and it colocalizes with the Na+,K+-ATPase to the basolateral membrane. Analysis of the levels of expression of sgk1 by Western blotting and immunohistochemistry indicates constitutive high expression under basal conditions. Approximately half of the basal level is maintained by glucocorticoids whereas physiological fluctuations of aldosterone produce minor changes in sgk1 abundance in adrenal-intact animals. These results do not support the notion that physiological changes of aldosterone concentration turn the expression of sgk1 'on and off' in the mammalian kidney. Additionally, localization of sgk1 to the basolateral membrane indicates that the effects mediated by sgk1 do not require a direct interaction with the ion channels and transporters whose activity is modulated, since most of these proteins are located in the apical membrane of renal epithelial cells.

Adrenalectomy↗
PubMed2003

L523S, an RNA-binding protein as a potential therapeutic target for lung cancer.

Approaches to vaccine-based immunotherapy of human cancer may ultimately require targets that are both tumour-specific and immunogenic. In order to generate specific antitumour immune responses to lung cancer, we have sought lung cancer-specific proteins that can be targeted for adjuvant vaccine therapy. By using a combination of cDNA subtraction and microarray analysis, we previously reported the identification of an RNA-binding protein within the KOC family, L523S, to be overexpressed in squamous cell cancers of the lung. We show here that L523S exhibits significant potential for vaccine immunotherapy of lung cancer. As an oncofetal protein, L523S is normally expressed in early embryonic tissues, yet it is re-expressed in a high percentage of nonsmall cell lung carcinoma. The specificity of L523S expression in lung cancer was demonstrated by both mRNA and protein measurements using real-time PCR, Western blot, and immunohistochemistry analyses. Furthermore, we show that immunological tolerance of L523S is naturally broken in lung cancer patients, as evidenced by detectable antibody responses to recombinant L523S protein in eight of 17 lung pleural effusions from lung cancer patients. Collectively, our studies suggest that L523S may be an important marker of malignant progression in human lung cancer, and further suggest that treatment approaches based on L523S as an immunogenic target are worthy of pursuit.

Biomarkers, Tumor↗
PubMed2003

Regulation of caldesmon activity by Cdc2 kinase plays an important role in maintaining membrane cortex integrity during cell division.

To study the mitosis-specific phosphorylation of caldesmon (CaD), we generated a mutant of the C-terminal fragment (amino acids 244-538) of human fibroblast CaD (CaD39-6F), as well as a mutant of the full-length CaD (CaD-6F), in which all six potential phosphorylation sites for Cdc2 kinase were abolished. The mitotic CaD39-6F-overexpressing cells required more time to progress from anaphase start to 50% cytokinesis, exhibited larger size, and abnormally formed numerous small blebs. In contrast, overexpression of the wild-type C-terminal fragment of CaD (CaD39) did not result in abnormal bleb formation, but led to larger size and prolonged the time requirement between anaphase start and 50% cytokinesis. Similar abnormal blebs were also observed in the CaD-6F-overexpressing cells. CaD-6F-overexpressing cells did not show larger size but required more time to progress from anaphase start to 50% cytokinesis. These results suggest that mitosis-specific phosphorylation of CaD plays a role in inhibiting bleb formation and that the N-terminal fragment of CaD is required for cell size determination.

Actins↗
PubMed2003

On the local and regional influence on ground-level ozone concentrations in Hong Kong.

Hong Kong is a densely populated city situated in the fast developing Pearl River Delta of southern China. In this study, the recent data on ozone (O3) and related air pollutants obtained at three sites in Hong Kong are analyzed to show the variations of O3 in urban, sub-urban and rural areas and the possible regional influences. Highest monthly averaged O3 was found at a northeastern rural site and lowest O3 level was observed at an urban site. The levels of NOx, CO, SO2 and PM10 showed a different spatial pattern with the highest level in the urban site and lowest at the rural site. Analysis of chemical species ratios such as SO2/NOx and CO/NOx indicated that the sites were under the influences of local and regional emissions to varying extents reflecting the characteristics of emission sources surround the respective sites. Seasonal pattern of O3 is examined. Low O3 level was found in summer and elevated levels occurred in autumn and spring. The latter appears different from the previous result obtained in 1996 indicating a single maximum occurring in autumn. Principal component analysis was used to further elucidate the relationships of air pollutants at each site. As expected, the O3 variation in the northeastern rural area was largely determined by regional chemical and transport processes, while the O3 variability at the southwestern suburban and urban sites were more influenced by local emissions. Despite the large difference in O3 levels across the sites, total potential ozone (O3+NO2) showed little variability. Cases of high O3 episodes were presented and elevated O3 levels were formed under the influence of tropical cyclone bringing in conditions of intense sunlight, high temperature and light winds. Elevated O3 levels were also found to correlate with enhanced ratio of SO2 to NOx, suggesting influence of regional emissions from the adjacent Pearl River Delta region.

Air Pollutants↗
PubMed2003

S, m, l, xl.

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Barrett Esophagus↗
PubMed2003

Effect of pH on the gelation properties of skim milk gels made from plant coagulants and chymosin.

The effect of three milk pH values, 6.0, 6.3 and 6.7, on gelation properties was monitored by small amplitude oscillatory rheology as well as a large deformation (yield) test for gels induced by the plant coagulants, Cynara cardunculus L. and Cynara humilis L., and chymosin. Gel microstructure was studied using confocal scanning laser microscopy. For each coagulant, a decrease in pH of milk resulted in a decrease in gelation time (tg), and an increase in the rate of increase in storage modulus (G'). At pH 6.0 and 6.3, plant coagulant-induced gels reached a maximum value in G' (G'max) followed by a decrease in G' values during the rest of the experiment, reflecting higher proteolytic activity of plant coagulants towards caseins as determined by SDS-PAGE. Gels produced at pH 6.0 and 6.3, exhibited a minimum in loss tangent (tan delta) followed by slight increase in tan delta during gel aging, that may have been associated with faster rearrangements of the gel network structure. In gels aged for approximately 6 h, the values for G', tan delta at low frequency (0.006 Hz) and yield stress were higher for chymosin than for plant-induced gels. For gels with the same pH value, no major differences were observed in microstructure between coagulants. Gels made at low pH values (6.3 and 6.0) appeared to have a denser or more interconnected structure than gels made at pH 6.7. Our results suggest that, at a low pH, the type of coagulant used in gelation is likely to have a considerably impact on gel/cheese structure.

Animals↗
PubMed2003

Use of multi-angle laser light scattering and size-exclusion chromatography to characterize the molecular weight and types of aggregates present in commercial whey protein products.

In this study, a range of commercial whey protein products were characterized by the use of size-exclusion chromatography coupled with a multi-angle laser light scattering (MALLS) detector. The MALLS system detected some very large-sized material that eluted close to void volume in all samples; this material was hardly detected by concentration detector. It was demonstrated by chitosan treatment that this peak was very small lipid globules or phospholipids, which gave the residual "cloudy" appearance in upper layers after ultracentrifugation of whey products. Composition, molecular weight, and the photo diode array (PDA) spectrum (200 to 400 nm) of the major protein peaks, including: beta-lactoglobulin (BLG), alpha-lactalbumin (ALA), bovine serum albumin (BSA), immunoglobulin G (IgG) and some minor components were analyzed. The molecular weight of BLG, ALA, BSA, and IgG peaks in whey protein isolates (WPI) were 2.3 to 3.7 x 10(4), 1.4 to 1.6 x 10(4), 4.8 to 6.7 x 10(4), and 1.2 to 2.5 x 10(5) Da, respectively. Compared with WPI, WPC has similar major proteins, but more large-sized residual lipid material and different minor constituents such as lactose and nonprotein nitrogen, depending on various commercial samples and protein content. An improved TCA-precipitation method was applied to quantify glycomacropeptide (GMP) in whey proteins, which demonstrated that there was a very low concentration of GMP in WPI manufactured using an ion-exchange process. The molecular weight of GMP was found to be approximately 8600 Da. Size-exclusion chromatography MALLS was demonstrated to be a powerful technique for detailed analysis of the molecular weight of various proteins, aggregates and minor components, such as GMP, in whey protein products.

Chromatography, Gel↗
PubMed2002

Influence of hyperosmotic shrinkage and beta-adrenergic stimulation on red blood cell volume regulation and oxygen binding properties in rainbow trout and carp.

Whole blood from rainbow trout and carp was subjected to hyperosmotic shock and subsequent beta-adrenergic stimulation (isoprenaline) at different oxygen tension ( PO(2)) and carbon dioxide tension ( PCO(2)) levels with the aim to evaluate changes in red blood cell (RBC) volume, pH and ion concentrations and their ultimate effect on blood O(2) transport characteristics. Hyperosmolality (addition of NaCl) induced RBC shrinkage, which was followed by a regulatory volume increase (RVI) that was larger at low than at high PO(2)and more complete in carp than in trout. Carp RBC showed practically full volume recovery within 140 min at low PO(2)and partial recovery at high PO(2), whereas RVI was partial under all PO(2)and PCO(2)conditions in trout. The RVI increased intracellular [Na(+)], water content, and, in carp, also pH (pHi), suggesting activation of Na(+)/H(+) exchange. In trout RBCs, activation of RVI was rapid but succeeded by deactivation. In carp RBCs, activation of Na(+) influx was slower but it continued, allowing full volume recovery. Shrinkage of the RBCs was associated with only minor decreases in blood oxygen saturation and oxygen affinity in both species. Thus, the oxygen affinity decrease expected on the basis of the increased concentration of intracellular haemoglobin and organic phosphates was small, and it appeared to some extent countered during RVI by an oxygen affinity increase via increased pHi. Addition of isoprenaline increased RBC volume and pHi and increased Hb oxygen saturation. The beta-adrenergic response was stronger at low compared to high PO(2) and at high compared to low PCO(2). The PO(2) dependency was largest in carp, whereas the PCO(2) (pH) dependency was more expressed in trout. The adrenergic response of trout RBCs was similar under isoosmotic and hyperosmotic conditions. In carp RBCs, the response was absent at high PO(2) under isoosmotic conditions, but interestingly it could be induced under hyperosmotic conditions. The data suggest that the RBC shrinkage occurring in fish moving from freshwater to seawater has minimal impact on blood O(2) binding properties.

Adaptation, Physiological↗
PubMed2002

Isoforms of soluble alpha-tubulin in oocytes and brain of the frog (genus Rana): changes during oocyte maturation.

Rana oocytes have previously been shown to contain much more soluble tubulin than does the brain, suggesting different assembly and disassembly dynamics of frog oocyte tubulin compared to that in brain. By using centrifugation, SDS-PAGE, two-dimensional gel electrophoresis and Western blots, probed with anti-alpha-tubulin monoclonal antibodies, polymorphic alpha-tubulins (isoforms) were compared in brains and follicle-enclosed oocytes of northern (Rana pipiens) and southern (R. berlandieri) frogs. Oocyte tubulin in both species had isoforms with greater ranges of isoelectric point (pI) than those of brain tubulins; in particular, the oocyte tubulin pIs ranged further into the acidic region of the isoelectric-focusing gels than corresponding brain tubulin. This difference may, in part, be responsible for the previously reported assembly differences between oocyte tubulin (undetectable assembly) and brain tubulin (high assembly). Isoforms of alpha-tubulin with relatively acidic pI were more abundant in northern frog brain and oocyte soluble extracts than in analogous extracts from southern frogs. Furthermore, additional acidic alpha-tubulin isoforms were found in progesterone-treated oocytes (i.e., eggs), indicating increased heterogeneity of acidic alpha-tubulin isoforms during oocyte meiotic maturation. Among northern frog oocyte soluble components fractionated on Superose-6b columns, tubulin complexes with apparent molecular mass of about 1800 kDa were found to contain acidic alpha-tubulin isoforms while the putative oligomeric tubulins with an apparent molecular mass of about 250 kDa contained an additional relatively basic alpha-tubulin isoform. The acidic alpha-tubulin isoforms, therefore, are proposed to be associated with cold-adaptable cells of brain and oocytes, and may also be involved in stabilization of large soluble tubulin complexes in oocytes of the northern frog.

Animals↗
PubMed2002

Adrenergic receptors, Na+/H+ exchange and volume regulation in lungfish erythrocytes.

Aestivation in African and South American lungfish (Protopterus and Lepidosiren, respectively) is associated with elevations of extracellular osmolarity. Osmotic shrinkage of Protopterus red blood cells (RBCs) caused a small but significant stimulation of the Na influx that was amiloride-sensitive. suggesting involvement of the Na+/H+ exchanger (NHE). The associated in vitro regulatory volume increase was insignificant within a time frame of 120 min, but the shrinkage-activated Na+ influx may be sufficient for slow regulatory volume increase during aestivation in vivo. Osmotic swelling of the RBCs induced an incomplete regulatory volume decrease that was statistically significant after 180 min. The RBCs of Protopterus were very large (mean cellular volume of 6939 +/- 294 microm3) and possessed 23,066 +/- 7,326 beta-adrenoceptors cell(-1) with a Kd value of 6.1 +/- 3.2 nM. The number of receptors per unit surface area of lungfish RBCs was calculated to be twice that of trout RBCs and 70% that of cod RBCs. There was, however, no adrenergic stimulation of the NHE in either Protopterus or Lepidosiren. Acidification of the extracellular medium also failed to activate the NHE.

Animals↗
PubMed2002

Differential expression of two tumor necrosis factor genes in rainbow trout, Oncorhynchus mykiss.

A second TNF gene (TNF2) has been cloned and sequenced in rainbow trout. In common with the first TNF gene isolated (TNF1), this gene is more TNF alpha-like than TNF beta-like. The full length cDNA is 1519bp, containing a 765bp open reading frame. The gene has four exons, of 380, 49, 60 and 1030bp, respectively. Analysis of the 5' flanking regions of TNF1 and TNF2 reveals several interesting differences in identified transcriptional regulatory elements, with a CATAAA box present 26bp upstream of the transcription start in both genes. Expression analysis in LPS stimulated macrophages has shown a much stronger expression of TNF2 relative to TNF1, with expression being detected earlier and lasting longer.

Amino Acid Sequence↗