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1.
Cancer Med ; 12(12): 13675-13686, 2023 06.
Article in English | MEDLINE | ID: mdl-37148545

ABSTRACT

BACKGROUND: Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries, with overall incidence increasing, particularly high-grade disease. There is sparse information regarding quality of life (QOL) in EC survivors with a focus on grade of disease. METHODS: A total of 259 women with EC diagnosed between 2016 and 2020 were identified via the Metropolitan Detroit Cancer Surveillance System and consented to enroll in the Detroit Research on Cancer Survivors cohort study (if African American, n = 138) or completed the baseline interview (if non-Hispanic white, n = 121). Each respondent provided information about their health history, educational attainment, health behaviors, and demographics. The Functional Assessment of Cancer Therapy-General (FACT-G) and Endometrial-specific (FACT-En) were used to assess QOL. RESULTS: Women diagnosed with high-grade (n = 112) and low-grade (n = 147) EC participated in this study. EC survivors with high-grade disease reported significantly lower QOL compared to survivors with low-grade disease (85 vs. 91, respectively, p value = 0.025) as assessed by the FACT-G. This difference was driven by lower physical and functional subscales among women with high-grade disease compared to those with low-grade disease (p value = 0.016 and p = 0.028, respectively). Interestingly, EC-specific QOL measures, as assessed by the FACT-En, did not differ by grade. CONCLUSION: Grade of disease impacts QOL in EC survivors, as well as socioeconomic, psychological, and physical factors. Most of these factors are amenable to interventions and should be assessed in patients after an EC diagnosis.


Subject(s)
Cancer Survivors , Endometrial Neoplasms , Female , Humans , Cancer Survivors/psychology , Quality of Life/psychology , Cohort Studies , Survivors/psychology , Endometrial Neoplasms/pathology
2.
Gynecol Oncol ; 133(1): 38-42, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24680590

ABSTRACT

OBJECTIVE: Endometrial cancer mortality disproportionately affects black women and whether greater prevalence of obesity plays a role in this disparity is unknown. We examine the effect of race on post-surgical complications, length of stay, and mortality specifically in a morbidly obese population. METHODS: Black and white women with endometrial cancer diagnosed from 1996 to 2012 were identified from the University Pathology Group database in Detroit, Michigan, and records were retrospectively reviewed to obtain clinicopathological, demographic, and surgical information. Analysis was limited to those with a body mass index of 40kg/m(2) or greater. Differences in the distribution of variables by race were assessed by chi-squared tests and t-tests. Kaplan-Meier and Cox regression analyses were performed to examine factors associated with mortality. RESULTS: 97 white and 89 black morbidly obese women were included in this analysis. Black women were more likely to have type II tumors (33.7% versus 15.5% of white women, p-value=0.003). Hypertension was more prevalent in black women (76.4% versus 58.8%, p-value=0.009), and they had longer hospital stays after surgery despite similar rates of open vs minimally invasive procedures and lymph node dissection (mean days=5.4) compared to whites (mean days=3.5, p-value=0.036). Wound infection was the most common complication (16.5% in whites and 14.4% in blacks, p-value=0.888). Blacks were more likely to suffer other complications, but overall the proportions did not differ by race. In univariate analyses, black women had higher risk of endometrial cancer-related death (p-value=0.090). No racial differences were noted in adjusted survival analyses. CONCLUSION: A more complete investigation, incorporating socio-demographic factors, is warranted to understand the effects of morbid obesity and race on endometrial cancer.


Subject(s)
Black or African American/statistics & numerical data , Carcinoma, Endometrioid/surgery , Carcinoma/surgery , Endometrial Neoplasms/surgery , Obesity, Morbid/ethnology , Postoperative Complications/ethnology , White People/statistics & numerical data , Adenocarcinoma, Clear Cell/ethnology , Adenocarcinoma, Clear Cell/mortality , Adenocarcinoma, Clear Cell/surgery , Adult , Carcinoma/ethnology , Carcinoma/mortality , Carcinoma, Endometrioid/ethnology , Carcinoma, Endometrioid/mortality , Endometrial Neoplasms/ethnology , Endometrial Neoplasms/mortality , Female , Humans , Hypertension/ethnology , Length of Stay/statistics & numerical data , Middle Aged , Proportional Hazards Models , Retrospective Studies , Surgical Wound Infection/ethnology , Survival Analysis , Treatment Outcome , Young Adult
3.
Lung Cancer ; 55(3): 255-62, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17174438

ABSTRACT

Polymorphisms in CYP1A1 and CYP1B1 genes in humans are associated with reduction of enzymatic activity towards several substrates, including those found in tobacco smoke. To investigate the potential role these polymorphisms have as modulators of early-onset lung cancer risk, a population-based case-control study involving early-onset lung cancer cases was performed. Biological samples were available for 383 individuals diagnosed prior to 50 years of age identified from the metropolitan Detroit Surveillance, Epidemiology and End Results (SEER) program and 449 age, race and sex-matched controls ascertained through random digit dialing. Genotype frequencies varied significantly by race for CYP1A1 Ile(462)Val and CYP1B1 Leu(432)Val genotypes, so all analyses were stratified by race. No association was seen between lung cancer risk and polymorphisms in CYP1A1 Msp1 or CYP1B1 Leu(432)Val for Caucasians or African Americans, after adjusting for age at diagnosis, sex, pack years of smoking and family history of lung cancer. In Caucasians, those with the IIe/Val genotype at CYP1A1 Ile(462)Val locus were at decreased risk of having lung cancer compared to those with the lle/lle genotype, after adjusting for age at diagnosis, sex, pack years of smoking and family history of cancer (OR=0.41 95% Cl 0.19-0.90). These results were not replicated among the African American population, nor were they modified by amount of smoking.


Subject(s)
Adenocarcinoma/ethnology , Aryl Hydrocarbon Hydroxylases/genetics , Black or African American/genetics , Cytochrome P-450 CYP1A1/genetics , Lung Neoplasms/ethnology , White People/genetics , Adenocarcinoma/genetics , Adult , Amino Acids, Branched-Chain/genetics , Case-Control Studies , Cytochrome P-450 CYP1B1 , Exons , Female , Genotype , Humans , Lung Neoplasms/genetics , Male , Polymorphism, Genetic , Smoking/ethnology
4.
Am J Epidemiol ; 164(11): 1027-42, 2006 Dec 01.
Article in English | MEDLINE | ID: mdl-17000715

ABSTRACT

Lung cancer is the most common malignancy in the Western world, and the main risk factor is tobacco smoking. Polymorphisms in metabolic genes may modulate the risk associated with environmental factors. The glutathione S-transferase theta 1 gene (GSTT1) is a particularly attractive candidate for lung cancer susceptibility because of its involvement in the metabolism of polycyclic aromatic hydrocarbons found in tobacco smoke and of other chemicals, pesticides, and industrial solvents. The frequency of the GSTT1 null genotype is lower among Caucasians (10-20%) than among Asians (50-60%). The authors present a meta- and a pooled analysis of case-control, genotype-based studies that examined the association between GSTT1 and lung cancer (34 studies, 7,629 cases and 10,087 controls for the meta-analysis; 34 studies, 7,044 cases and 10,000 controls for the pooled analysis). No association was observed between GSTT1 deletion and lung cancer for Caucasians (odds ratio (OR) = 0.99, 95% confidence interval (CI): 0.87, 1.12); for Asians, a positive association was found (OR = 1.28, 95% CI: 1.10, 1.49). In the pooled analysis, the odds ratios were not significant for either Asians (OR = 0.97, 95% CI: 0.83, 1.13) or Caucasians (OR = 1.09, 95% CI: 0.99, 1.21). No significant interaction was observed between GSTT1 and smoking on lung cancer, whereas GSTT1 appeared to modulate occupational-related lung cancer.


Subject(s)
Glutathione Transferase/genetics , Lung Neoplasms/enzymology , Lung Neoplasms/genetics , Asian People/statistics & numerical data , Case-Control Studies , Data Interpretation, Statistical , Genetic Predisposition to Disease , Genetic Variation , Genotype , Glutathione Transferase/physiology , Humans , Lung Neoplasms/ethnology , Polymorphism, Genetic , Risk Factors , Smoking/adverse effects , White People/statistics & numerical data
5.
Lung Cancer ; 52(3): 273-9, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16567020

ABSTRACT

Carcinoid tumors of the lung were first described in 1937, yet little is known about their etiology. The aim of the present investigation was to determine if there was excess risk of secondary cancers in a population-based sample after a lung carcinoid tumor diagnosis which may provide insight to the etiology. Subjects were 1882 cases diagnosed with carcinoid tumors of the lung between 1988 and 2000 whose information was obtained from the Surveillance, Epidemiology and End Results (SEER) Program database. Standardized incidence ratios were calculated by dividing the observed number of second primary cancers by the expected number of cancers. Excess risk of breast cancer was seen following diagnosis of a carcinoid tumor (SIR=1.80 95% CI 1.22-2.55). When stratified by time after diagnosis, excess risk of breast cancers in women was seen in the first 5 years after carcinoid diagnosis (SIR=1.68 95% CI 1.08-2.50) but fewer than expected breast cancers were diagnosed greater than 5 years after carcinoid diagnosis (SIR=0.29 95% CI 0.09-0.68). Prostate cancers also occurred 2.8 times more often than expected (95% CI 1.66-4.43), with risk being elevated only in the first 5 years post-carcinoid diagnosis. Development of lung carcinoids may be the result of genetic predisposition or environmental exposures, particularly those that are hormonally related. The role of genetics and sex hormones in lung carcinoid development, as well as the identification of other risk factors, should be explored.


Subject(s)
Breast Neoplasms/epidemiology , Carcinoid Tumor/epidemiology , Lung Neoplasms/epidemiology , Neoplasms, Second Primary/epidemiology , Prostatic Neoplasms/epidemiology , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Breast Neoplasms/history , Carcinoid Tumor/diagnosis , Carcinoid Tumor/genetics , Carcinoid Tumor/history , Female , History, 20th Century , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/genetics , Lung Neoplasms/history , Male , Neoplasms, Second Primary/diagnosis , Neoplasms, Second Primary/genetics , Neoplasms, Second Primary/history , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/history , Retrospective Studies , Risk Factors , Time Factors
6.
Carcinogenesis ; 26(12): 2207-12, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16051642

ABSTRACT

The cytochrome P450 (CYP) superfamily of enzymes catalyse one of the first steps in the metabolism of carcinogens such as polycyclic aromatic hydrocarbons, nitroaromatics and arylamines. Polymorphisms within the CYP1A1 gene have been shown to be associated with lung cancer risk, predominantly among Asian populations. Despite functional evidence of a possible role of CYP1B1 in lung cancer susceptibility, only a few studies have evaluated polymorphisms in this gene in relation to lung cancer susceptibility. This population-based study evaluates polymorphisms in both of these CYP genes within never smokers, most of whom had environmental tobacco smoke (ETS) exposure. Cases (n = 160) were identified through the metropolitan Detroit Surveillance, Epidemiology and End Results program, and age, sex and race-matched population-based controls (n = 181) were identified using random digit dialing. Neither CYP1A1 MspI nor CYP1A1 Ile(462)Val was associated with lung cancer susceptibility among Caucasians or African-Americans. Among Caucasians, however, CYP1B1 Leu(432)Val was significantly associated with lung cancer susceptibility odds ratio (OR) for at least one valine allele = 2.87 [95% confidence interval (CI) 1.63-5.07]. Combinations of this Phase I enzyme polymorphism along with selected Phase II enzyme polymorphisms (GSTM1 null, GSTP1 Ile(105)Val and NQO1 C(609)T) were evaluated. The combination of CYP1B1 Leu(432)Val and NQO1 C(609)T appeared to be associated with the highest risk of lung cancer (OR = 4.14, 95% CI 1.60-10.74), although no combinations differed significantly from the risk associated with CYP1B1 Leu(432)Val alone. When individuals were stratified by household ETS exposure (yes/no), CYP1B1 Leu(432)Val alone and in combination with Phase II enzyme polymorphisms was more strongly associated with increased lung cancer susceptibility among those with at least some household ETS exposure. Additional studies will be required to further validate these findings among never smokers and to evaluate the effects of this polymorphism among smoking populations as well.


Subject(s)
Aryl Hydrocarbon Hydroxylases/genetics , Cytochrome P-450 CYP1A1/genetics , Lung Neoplasms/epidemiology , Lung Neoplasms/genetics , Polymorphism, Genetic , Tobacco Smoke Pollution/adverse effects , Adenocarcinoma/genetics , Black or African American/genetics , Alleles , Carcinoma, Large Cell/genetics , Carcinoma, Small Cell/genetics , Carcinoma, Squamous Cell/genetics , Case-Control Studies , Cytochrome P-450 CYP1B1 , Female , Genetic Predisposition to Disease , Genotype , Glutathione S-Transferase pi/genetics , Glutathione Transferase/genetics , Humans , Male , Middle Aged , NAD(P)H Dehydrogenase (Quinone)/genetics , Risk Factors , SEER Program , Smoking , United States/epidemiology , White People/genetics
7.
Carcinogenesis ; 26(4): 811-9, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15661806

ABSTRACT

Polymorphisms in GSTM1, GSTT1 and GSTP1 genes in humans are associated with the reduction of enzymatic activity toward several substrates, including those in tobacco smoke. To investigate the potential role these polymorphisms have, as modulators of early-onset lung cancer risk, a population-based case-control study involving early-onset lung cancer cases was performed. Biological samples were available for 350 individuals diagnosed <50 years of age identified from the metropolitan Detroit Surveillance, Epidemiology and End Results (SEER) program and 410 cases of age, race and sex-matched controls ascertained through random digit dialing. African Americans carrying at least one G allele at the GSTP1 locus were 2.9-fold more likely to have lung cancer compared with African Americans without a G allele after adjustment for age, sex, pack years of smoking and history of lung cancer in a first-degree relative (95% CI 1.29-6.20). African Americans with either one or two risk genotypes at the GSTM1 and GSTP1 loci were at increased risk of having lung cancer compared with those having fully functional GSTM1 and GSTP1 genes (OR = 2.8, 95% CI 1.1-7.2 and OR = 4.0, 95% CI 1.3-12.2, respectively). No significant single gene associations between GSTM1, GSTT1 or GSTP1 and early-onset lung cancer were identified in Caucasians, after adjusting for age, sex, pack years and family history of lung cancer. However, our results suggest that specific combinations of glutathione S-transferase polymorphisms increase the risk of early-onset of lung cancer. Joint analysis of these genotypes may identify individuals who are at a higher risk of developing early-onset lung cancer with a greater certainty than single gene studies.


Subject(s)
Black or African American/genetics , Glutathione Transferase/genetics , Isoenzymes/genetics , Lung Neoplasms/ethnology , Lung Neoplasms/enzymology , White People/genetics , Adult , Age of Onset , Carcinoma, Large Cell/enzymology , Carcinoma, Large Cell/ethnology , Carcinoma, Large Cell/genetics , Carcinoma, Small Cell/enzymology , Carcinoma, Small Cell/ethnology , Carcinoma, Small Cell/genetics , Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/ethnology , Carcinoma, Squamous Cell/genetics , Case-Control Studies , Female , Genetic Predisposition to Disease , Genetics, Population , Genotype , Glutathione S-Transferase pi , Humans , Lung Neoplasms/genetics , Male , Risk Factors , SEER Program
8.
Carcinogenesis ; 26(2): 381-6, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15498787

ABSTRACT

The NAD(P)H:quinone oxidoreductase 1 gene, NQO1, contains a C to T transition at amino acid codon 187, which results in very low enzymatic activity. Previous studies of the association between NQO1 genotype and lung cancer have had mixed findings. This population-based case control study examines the association between NQO1 genotype and lung cancer in the largest sample of never smokers (<100 cigarettes, lifetime) to date. Cases (n = 161) were identified through the metropolitan Detroit Surveillance, Epidemiology and End Results (SEER) program, and 5-year age- and race-matched population-based controls (n = 173) were identified using random digit dialing. Allele frequencies of C and T, respectively, were 0.79 and 0.21 in Caucasians, and 0.84 and 0.16 in African Americans. Among those diagnosed aged >/=50 years, C/T and T/T genotyped individuals had 0.48 times lower lung cancer risk than individuals with C/C genotype (95% CI: 0.27-0.87). There was a non-significant suggestion of a protective effect associated with the T allele among those with a history of environmental tobacco smoke exposure (OR = 0.57, 95% CI: 0.32-1.03) but not among those without (OR = 0.98, 95% CI: 0.41-2.38). Sex, race, family history of lung cancer and histologic type did not modify the effect of NQO1 genotype on lung cancer risk. The observed risk reductions may be attributable to the greatly reduced procarcinogen activating of NAD(P)H:quinone oxidoreductase 1 in individuals with at least one copy of the T allele.


Subject(s)
Alleles , Genetic Predisposition to Disease , Lung Neoplasms/genetics , NAD(P)H Dehydrogenase (Quinone)/genetics , Smoking/adverse effects , Adult , Aged , Case-Control Studies , Female , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics
9.
Carcinogenesis ; 26(2): 395-401, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15528218

ABSTRACT

Glutathione S-transferases detoxify polycyclic aromatic hydrocarbons found in tobacco smoke by glutathione conjugation. Polymorphisms within the GSTM1, GSTT1 and GSTP1 genes, coding for enzymes with deficient or reduced activity, have been studied as potential modifiers of lung cancer risk. It is hypothesized that risk associated with potential susceptibility gene polymorphisms might be most evident at low levels of exposure. Never smokers developing lung cancer represent a highly susceptible subset of the population, exposed to tobacco carcinogens only through environmental tobacco smoke. This population-based case-control study examines the association between GSTM1, GSTT1 and GSTP1 genotypes and lung cancer in one of the largest samples of never smokers to date. Cases (n = 166) were identified through the metropolitan Detroit Surveillance, Epidemiology and End Results (SEER) program and age- and race-matched population-based controls (n = 181) were identified using random digit dialing. Overall, there was no significant association between single or combinations of genotypes at GSTM1, GSTT1 or GSTP1 and lung cancer risk after adjustment for age, race, sex and household ETS exposure in years. However, in never smokers exposed to 20 or more years of household ETS, carrying the GSTM1 null genotype was associated with a 2.3-fold increase in risk [95% confidence interval (CI) 1.05-5.13]. Individuals in this high ETS exposure category carrying the GSTM1 null and the GSTP1 Val allele were at over 4-fold increased risk of developing lung cancer (OR = 4.56, 95% CI: 1.21-17.21). These findings suggest that in the presence of ETS, the GSTM1 genotype both alone and in combination with the GSTP1 genotype alters the risk of developing lung cancer among never smokers.


Subject(s)
Glutathione Transferase/genetics , Lung Neoplasms/genetics , Polymorphism, Genetic , Tobacco Smoke Pollution/adverse effects , Adult , Aged , Case-Control Studies , Female , Genetic Predisposition to Disease , Genotype , Glutathione S-Transferase pi , Humans , Isoenzymes/genetics , Male , Middle Aged
10.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 9): 1238-50, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11526315

ABSTRACT

The X-ray crystal structure at 2.0 A resolution of a DNA molecule complexed with the N-terminal fragment of Moloney murine leukemia virus reverse transcriptase (MMLV RT) has been determined. This method allows the study of nucleic acids in a unique and largely unfettered environment without the complicated lattice interactions typically observed in DNA-only crystal structures. Molecular-replacement phasing using only the protein provided readily interpretable electron density with no model bias for the DNA. The asymmetric unit of the structure consists of the protein molecule bound to the blunt end of a DNA 6/10-mer, which is composed of a six-base strand (5'-GTCGTC-3') and a ten-base strand (3'-CAGCAGGGCA-5'), resulting in a six-base-pair duplex with a four-base single-stranded overhang. In the crystal structure, the bases of the overhang reciprocally pair to yield a doubly nicked pseudo-hexadecamer primarily B-form DNA molecule. The pairing between the single strands gives two standard (G-C) Watson-Crick pairs and two G(anti)-A(anti) mispairs. The mispairs reside in a G-C-rich environment and the three consecutive guanines on the 10-mer impart interesting structural features to the pseudo-hexadecamer, such as the preference for a guanine stack, stretching the C-G base pairs flanking the mispair to the point of loss of intra-base-pair hydrogen bonding. The DNA was designed for the purpose of comparison with a previous structure, which was determined in the same crystal lattice. In all of the authors' previous fragment-DNA complexes, the nucleotide at the blunt-ended 3'-hydroxyl was a purine. Consistent with the proposed mechanistic role of interactions with the 3'-hydroxyl in processive DNA synthesis by RT, it was found that a pyrimidine at this position in the DNA makes indentical interactions with the strictly conserved Gly191 and the main chain of Leu115 of MMLV RT.


Subject(s)
DNA/chemistry , Moloney murine leukemia virus/enzymology , Poly G/chemistry , RNA-Directed DNA Polymerase/chemistry , Base Pair Mismatch , Crystallization , Crystallography, X-Ray , Guanine/chemistry , Models, Molecular , Nucleic Acid Conformation , Peptide Fragments/chemistry , Protein Conformation , Protein Structure, Tertiary
11.
Acta Crystallogr D Biol Crystallogr ; 56(Pt 9): 1120-31, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10957631

ABSTRACT

Complexation with the N-terminal fragment of Moloney murine leukemia virus reverse transcriptase offers a novel method of obtaining crystal structures of nucleic acid duplexes, which can be phased by molecular replacement. This method is somewhat similar to the method of using a monoclonal antibody Fab fragment complexed to the molecule of interest in order to obtain crystals suitable for X-ray crystallographic analysis. Here a novel DNA structure including two G-A mispairs in a pseudo-hexadecamer determined at 2.3 A resolution in a complex with the N-terminal fragment is reported. This structure has an asymmetric unit consisting of the protein molecule bound to the blunt end of a DNA 6/10-mer, which is composed of a six-base strand (5'-CTCGTG-3') and a ten-base strand (3'-GAGCACGGCA-5'). The 6/10-mer is thus composed of a six-base-pair duplex with a four-base single-stranded overhang. In the crystal structure, the bases of the overhang are reciprocally paired (symmetry element -x - 1, -y, z), yielding a doubly nicked pseudo-hexadecamer primarily B-form DNA molecule, which has some interesting A-like structural features. The pairing between the single strands results in two standard (G-C) Watson-Crick pairs and two G-A mispairs. The structural DNA model can accommodate either a standard syn or a standard anti conformation for the 5'-terminal adenine of the ten-base strand of the DNA based on analysis of simulated-annealing omit maps. Although the DNA model here includes nicks in the phosphodiester backbone, modeling of an intact phosphodiester backbone results in a very similar DNA model and indicates that the structure is biologically relevant.


Subject(s)
Base Pair Mismatch , DNA/chemistry , Moloney murine leukemia virus/enzymology , Peptide Fragments/chemistry , RNA-Directed DNA Polymerase/chemistry , Adenine/chemistry , Carbohydrate Conformation , Crystallization , Crystallography, X-Ray , Deoxyribose/chemistry , Guanine/chemistry , Models, Molecular , Nucleic Acid Conformation , Protein Conformation
12.
J Mol Biol ; 296(2): 613-32, 2000 Feb 18.
Article in English | MEDLINE | ID: mdl-10669612

ABSTRACT

Reverse transcriptase (RT) serves as the replicative polymerase for retroviruses by using RNA and DNA-directed DNA polymerase activities coupled with a ribonuclease H activity to synthesize a double-stranded DNA copy of the single-stranded RNA genome. In an effort to obtain detailed structural information about nucleic acid interactions with reverse transcriptase, we have determined crystal structures at 2.3 A resolution of an N-terminal fragment from Moloney murine leukemia virus reverse transcriptase complexed to blunt-ended DNA in three distinct lattices. This fragment includes the fingers and palm domains from Moloney murine leukemia virus reverse transcriptase. We have also determined the crystal structure at 3.0 A resolution of the fragment complexed to DNA with a single-stranded template overhang resembling a template-primer substrate. Protein-DNA interactions, which are nearly identical in each of the three lattices, involve four conserved residues in the fingers domain, Asp114, Arg116, Asn119 and Gly191. DNA atoms involved in the interactions include the 3'-OH group from the primer strand and minor groove base atoms and sugar atoms from the n-2 and n-3 positions of the template strand, where n is the template base that would pair with an incoming nucleotide. The single-stranded template overhang adopts two different conformations in the asymmetric unit interacting with residues in the beta4-beta5 loop (beta3-beta4 in HIV-1 RT). Our fragment-DNA complexes are distinct from previously reported complexes of DNA bound to HIV-1 RT but related in the types of interactions formed between protein and DNA. In addition, the DNA in all of these complexes is bound in the same cleft of the enzyme. Through site-directed mutagenesis, we have substituted residues that are involved in binding DNA in our crystal structures and have characterized the resulting enzymes. We now propose that nucleic acid binding to the fingers domain may play a role in translocation of nucleic acid during processive DNA synthesis and suggest that our complex may represent an intermediate in this process.


Subject(s)
DNA Primers/metabolism , Moloney murine leukemia virus/enzymology , Peptide Fragments/chemistry , Peptide Fragments/metabolism , RNA-Directed DNA Polymerase/chemistry , RNA-Directed DNA Polymerase/metabolism , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , Biopolymers/chemistry , Biopolymers/genetics , Biopolymers/metabolism , Conserved Sequence/genetics , Crystallization , Crystallography, X-Ray , DNA/biosynthesis , DNA/chemistry , DNA/genetics , DNA/metabolism , DNA Primers/chemistry , DNA Primers/genetics , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , HIV Reverse Transcriptase/chemistry , HIV Reverse Transcriptase/metabolism , Hydrogen Bonding , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , Nucleic Acid Conformation , Peptide Fragments/genetics , Protein Structure, Tertiary , RNA, Messenger/chemistry , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA-Directed DNA Polymerase/genetics , Rabbits , Templates, Genetic
17.
Birth Defects Orig Artic Ser ; 10(4): 44-50, 1974.
Article in English | MEDLINE | ID: mdl-4470906

ABSTRACT

In those children with thoracic asphyxiant dystrophy, a genetically determined disorder, who survive infancy, the development of renal disease may be life-threatening. This report will present data obtained in six patients from three families which deals with the renal abnormalities in thoracic asphyxiant dystrophy. Both functional and anatomic abnormalities are described. Abnormalities in solute transport in the proximal tubule may be the earliest sign of renal dysfunction in this syndrome. Early glomerular changes may be more important than previously recognized. Finally, the various phenotypic expressions of this disorder are considered.


Subject(s)
Kidney Diseases/etiology , Osteochondrodysplasias/complications , Thorax/abnormalities , Acidosis, Renal Tubular/etiology , Adolescent , Child , Child, Preschool , Glomerular Filtration Rate , Humans , Hydrogen-Ion Concentration , Infant , Infant, Newborn , Inulin , Kidney/pathology
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