Providing telemedicine services to persons living with HIV in an urban community: a demonstration project

Although HIV incidence and mortality rates have declined over the past 20 years, HIV health disparities continue to persist among patients living in urban communities. Barriers to proficient health outcomes for persons with HIV (PWH) in urban communities include lack of access to care, resulting from limited transportation or clinic availability. While healthcare systems in rural communities provide telemedicine (TM) services to PWH to eliminate transportation and accessibility barriers, few examples exist regarding TM use for PWH in urban communities. This project's goal was to increase the provision of healthcare services in an urban setting to PWH, using TM. As guided by "Integration of Healthcare Delivery Service" theories and key principles, we created an integration framework comprised of several simultaneous, overlapping activities to include: (1) capacity building (2) clinical standardization (3) community and patient engagement and (4) evaluation performance and measurements. This paper describes major activities involved with developing, implementing and evaluating a TM program for PWH. We discuss results, challenges, and lessons learned from integrating this program into our existing healthcare system.

Intergenerational Influence of African American, Caribbean and Hispanic/Latino Adults Regarding Decision to Participate in Health-Related Research

Introduction: Identifying effective strategies to enroll African American, Caribbean, and Hispanic/Latino adults ≥65 years of age in health research is a public health priority. This study aimed to explore intergenerational influence (IGI) among these populations living throughout Florida. Methods: African American, Caribbean, and Hispanic/Latino adults ≥65 years of age and a trusted family member/friend between 25-64 years participated in virtual listening sessions (LS). Culturally matched facilitators used a semi-structured guide to lead LS that was recorded, transcribed, and uploaded into NVivo©. The constant comparative method was used for analysis. Results: 363 African American, Caribbean, and Hispanic/Latino participated in LS. Five (5) themes relate to IGI emerged: (1) parent-child relationships; (2) family caregiving/parental illness experiences; (3) historical research maltreatment; (4) transfer of cultural knowledge; and (5) future generations. Discussion: Our findings support that IGI can be leveraged to increase the participation of African American, Caribbean, and Hispanic/Latino older adults in health research.

Florida-California Cancer Health Equity Center (CaRE2) Community Scientist Research Advocacy Program

The Community Scientist Program (CSP), a model connecting researchers with community members, is effective to inform and involve the general population in health-related clinical research. Given the existing cancer disparities among Black/African American and Hispanic/Latino/a populations, more models describing how cancer-related CSPs are designed, implemented, and evaluated are needed. The Florida-California Cancer Research, Education and Engagement (CaRE2) Health Equity Center is a tri-institutional, bicoastal center created to eliminate cancer health disparities among Black/African American and Hispanic/Latino/a populations living in California and in Florida. The CaRE2 Center created a Community Scientist Research Advocacy (CSRA) training program for community members to become cancer research advocates. The CSRA program is currently a 13-week program conducted 100% virtually with all materials provided in English and Spanish for participants to learn more about prostate, lung, and pancreas cancers, ongoing research at CaRE2, and ways to share cancer research throughout their communities. Participants attend didactic lectures on cancer research during weeks 1-5. In week 4, participants join CSRA self-selected groups based on cancer-related topics of interest. Each group presents their cancer-related advocacy project developed during weeks 5-12 at the final session. In this paper, we describe the CaRE2 Health Equity Center's CSRA program, share results, and discuss opportunities for improvement in future program evaluation as well as replication of this model in other communities.

Training Community African American and Hispanic/Latino/a Advocates on Prostate Cancer (PCa): a Multicultural and Bicoastal Approach

African American communities are disproportionately impacted by prostate cancer (PCa) compared to other racial/ethnic groups. Whereas the incidence of PCa in Hispanic/Latino men is lower than the incidence in non-Hispanic/Latino White men, Hispanic/Latino men are more likely to be diagnosed with PCa in late stages, and less likely to be knowledgeable about PCa, resulting in significant disparities. We developed, culturally adapted, translated, implemented, and evaluated a PCa Cancer Advocacy Training in African American and Hispanic/Latino/a communities. Culturally and language specific content for African American and Hispanic/Latino/a patients on PCa causes, risk factors, epidemiology, detection, diagnosis, and treatment were delivered through a workshop and simultaneously broadcasted in Spanish in Los Angeles County (n = 29) and in English in Tallahassee, FL (n = 9). Pre- and posttest surveys assessed impact. Pre vs post differences were statistically significant in knowledge (5.0 ± 1.6 vs 6.3 ± 1.1) and advocacy intentions (3.9 ± 0.9 vs 4.3 ± 0.8), on correctly identifying warning signs for PCa (50% vs 87%), intent to inform and educate about PCa within the next 3 months (69% vs 95%), to ensure that high-quality research is sensitive to the priorities of patients (63% vs 84%), to help increase patient recruitment, compliance, and retention for clinical trials within the next month (62% vs 84%), intent to engage in PCa patient education within the next 3 months (67% vs 92%), and in engaging in PCa community outreach within the next 3 months (67% vs 94%). There were no significant differences due to race/ethnicity. The Cancer Advocacy Training led to increased knowledge, awareness, and intention to engage in advocacy regarding PCa in the next 3 months. Results suggest that delivering culturally and language specific educational information increases engagement of Hispanic/Latino/a and African American patient/community advocates.

Smart Meds: Using Pharmacists to Address Health Literacy Disparities Among Medically- and Socially-Vulnerable Populations

Patients in historically underserved communities are most vulnerable to uncontrolled chronic conditions and report a lack of health knowledge to manage them. This report aims to describe the development of SMART MEDS, a pharmacy-led program implemented to address health literacy disparities among medically and socially vulnerable patients.

VOICES OF OUR ELDERS: ATTITUDES, BELIEFS, AND PERSPECTIVES ABOUT RESEARCH IN MINORITY OLDER ADULTS

The U.S. Census Bureau projects that the numbers of adults 65 and older will double from 46 million in 2020 to 90 million by 2050, thus representing the fastest growing segment of the population. However, older adults, especially those from minority groups, remain underrepresented in clinical research. It is imperative to understand what older adults believe about research and research participation to enhance recruitment efforts. The aim of this presentation is to present preliminary findings from our qualitative study which explored the attitudes, beliefs, and perspectives of older minority adults regarding research and research participation. We conducted 12 focus groups via Zoom, in South Florida with minority adults (African American, Caribbean, Hispanic) over the age of 65 (N=49). An interview guide was used to query the participants about their attitudes, beliefs, and perspectives of research and research participation. Focus groups were video-recorded and transcribed. NVivo software was used for data management and analysis. We found that participants: 1) thought research was necessary to expand understanding and knowledge of health conditions; 2) stated research should be conducted by trusted scientific institutions; 3) relied heavily on their adult children for advice regarding research participation; 4) expressed reluctancy regarding invasive procedures; and 5) were influenced by personal experiences when considering research participation. Our preliminary findings suggest that older minority adults believe in the value of research, however, may be hesitant about participating. We propose continued strategies aimed at increasing engagement of minority older adults into health research.

Promoting weight-loss maintenance among Black women primary care patients: A cluster RCT of a culturally sensitive versus standard behavioural approach

The prevalence of obesity is higher among Black women (56.6%) compared to Hispanic women (50%) and non-Hispanic White women (42%). Notably, interventions to reduce obesity typically result in initial weight loss that is not maintained. This study tested (a) the effectiveness of a 6-month Health-Smart Weight Loss (HSWL) Program for Black women patients with obesity implemented by community health workers (CHWs) within primary care clinics and (b) the comparative effectiveness of two 12-month physician-implemented weight loss maintenance programs-a Patient-Centred Culturally Sensitive Weight Loss Maintenance Program (PCCS-WLM Program) and a Standard Behavioural Weight Loss Maintenance Program (SB-WLM Program). Black women patients (N = 683) with obesity from 20 community primary care clinics participated in the HSWL Program and were then randomized to either maintenance program. The HSWL Program led to significant weight loss (i.e., 2.7 pounds, 1.22 kg, p < .01, -1.1%) among the participants. Participants in both the PCCS-WLM Program and the SB-WLM Program maintained their weight loss; however, at month 18, participants in the PCCS-WLM Program had a significantly lower weight than those in the SB-WLM (i.e., 231.9 vs. 239.4 pounds or 105.19 vs. 108.59 kg). This study suggests that (a) the HSWL Program can produce significant weight loss among Black women patients with obesity when implemented in primary care clinics by CHWs, and (b) primary care physicians can be trained to successfully promote weight loss maintenance among their Black women patients.

Engaging primary care patients with existing online tools for weight loss: A pilot trial

Objective

Free online tools show potential for promoting weight loss at a low cost, but there is limited evidence about how to effectively engage patients with them. To address this, a low‐dose, flexible intervention was developed that aims to enhance weight‐related discussions with primary care providers (PCPs) and engage patients with an organic (i.e., not researcher‐created) weight loss‐focused social media community and online self‐monitoring tool. Feasibility and acceptability of the intervention was evaluated in a single‐arm, 12‐week pilot.

Methods

PCPs were recruited at two clinics, then PCP's patients with upcoming appointments were identified and recruited. Patients received an interactive online kickoff before their scheduled primary care appointment, then 8 follow‐up messages over 12 weeks via email or their electronic health record patient portal. Patients completed assessments at baseline, post‐appointment, and week 12. Primary care providers and patients completed semi‐structured interviews.

Results

All PCPs approached enrolled (n = 6); patient recruitment was on track to meet the study goal prior to COVID‐19 restrictions, and n = 27 patients enrolled. Patient satisfaction with the pre‐appointment kickoff was high. Twenty‐four patients reported discussing weight‐related topics at their primary care appointment and all were satisfied with the discussion. Twenty‐two patients completed 12‐week assessments. Of these, 15 reported engaging with the self‐monitoring tool and 9 with the social media community. Patient interviews revealed reasons for low social media community engagement, including perceived lack of fit. On average, patients with available data (n = 21) lost 2.4 ± 4.1% of baseline weight, and 28.6% of these patients lost ≥3% of baseline weight. Primary care providers reported high intervention satisfaction.

Conclusions

The intervention and trial design show potential, although additional strategies are needed to promote tool engagement.

Striking a Balance between Work and Play: The Effects of Work-Life Interference and Burnout on Faculty Turnover Intentions and Career Satisfaction

BACKGROUND

The interactions between work and personal life are important for ensuring well-being, especially during COVID-19 where the lines between work and home are blurred. Work-life interference/imbalance can result in work-related burnout, which has been shown to have negative effects on faculty members' physical and psychological health. Although our understanding of burnout has advanced considerably in recent years, little is known about the effects of burnout on nursing faculty turnover intentions and career satisfaction.

OBJECTIVE

To test a hypothesized model examining the effects of work-life interference on nursing faculty burnout (emotional exhaustion and cynicism), turnover intentions and, ultimately, career satisfaction.

DESIGN

A predictive cross-sectional design was used.

SETTINGS

An online national survey of nursing faculty members was administered throughout Canada in summer 2021.

PARTICIPANTS

Nursing faculty who held full-time or part-time positions in Canadian academic settings were invited via email to participate in the study.

METHODS

Data were collected from an anonymous survey housed on Qualtrics. Descriptive statistics and reliability estimates were computed. The hypothesized model was tested using structural equation modeling.

RESULTS

Data suggest that work-life interference significantly increases burnout which contributes to both higher turnover intentions and lower career satisfaction. Turnover intentions, in turn, decrease career satisfaction.

CONCLUSIONS

The findings add to the growing body of literature linking burnout to turnover and dissatisfaction, highlighting key antecedents and/or drivers of burnout among nurse academics. These results provide suggestions for suitable areas for the development of interventions and policies within the organizational structure to reduce the risk of burnout during and post-COVID-19 and improve faculty retention.

Abstract PO-059: Multifaceted approaches to engaging Black and Latinx populations: From bed to bedside

INTRODUCTION The Cancer Research Education and Engagement (CaRE2) Health Equity Center seeks to eliminate cancer disparities within Black and Latinx communities through research, training, education, and community engagement. The goal of this presentation is to share the unique model of community engagement that was implemented by the CaRE2 Center's Community Outreach Core (COC) during the COVID-19 pandemic. METHODS During the COVID-19 pandemic, the COC hosted community outreach events to address prostate and pancreatic cancer disparities. We overcame the challenges of COVID-19 by hosting these programs over Zoom, Facebook, and Twitter and allowing participants to interact and ask questions. The use of these platforms allowed us to develop and implement the innovative “bed to bedside” model, which allowed participants to gain a well-rounded understanding of the cancer process from cancer survivors, physicians, and researchers of color. The goal of these events were to 1) increase awareness of the importance of prostate and pancreatic cancer screening, 2) educate patients and community members about potential prostate and pancreatic cancer treatments, 3) raise awareness on prostate and pancreatic cancer research, and 4) address the causes and solutions to prostate and pancreatic cancer disparities in the Black and Latinx community. RESULT A total of 4 events were conducted between September and November of 2021, reaching a total of 30 persons directly and about 30 more through social media. At each event, evidence-based prostate cancer and pancreatic cancer education was disseminated. Of the attendees, 48% identified as Black or African American and 14% as Latino(x). Attendees were given the option to provide feedback and 90% of attendees agreed or strongly agreed that the presentations met their expectations. One benefit of conducting outreach activities via these platforms was the ability for more individuals to attend and the elimination of transportation barriers. Participants reported that attending virtually was easy to navigate and provided a suitable environment given the ongoing pandemic. Participants also reported that they enjoyed the “bed to bedside” model and shared that hearing from a survivor of color led to them feeling more comfortable in considering cancer screening. CONCLUSION The Care2 COC, in partnership with the community, is addressing disparities in the Black and Latinx population. One of the barriers that we had to overcome was continuing community outreach during the COVID-19 pandemic. The decision to provide health education outreach over social platforms, was essential to maintain our reach and impact. This allowed for the implementation of the “bed to bedside” model that included the different perspectives of care. We concluded that this model was effective and helped normalize the treatment process. We also concluded that outreach to the community should continue to provide cancer information via virtual formats especially as the COVID-19 related incidence and mortality begins to increase.

Citation Format: Jessica Otero, Fern Webb, Folakemi Odedina, Nissa Askins, Linda Behar-Horenstein, Lourdes Baez-Conde, Mariana Stern, Sandra Suther, Renee Reams. Multifaceted approaches to engaging Black and Latinx populations: From bed to bedside [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-059.

Prevalence of epithelial abnormalities and high-risk human papilloma virus in cervicovaginal Pap smears of population subgroups as a guide toward evidence-based best practice

BACKGROUND

The 2012 American Society for Colposcopy and Cervical Pathology Consensus Guidelines provide information for managing abnormal cervical cancer screening tests and cancer precursors. According to these guidelines for Pap smear diagnosis of Atypical squamous cells of undetermined significance, reflex high risk (HR) human papilloma virus (HPV) genotyping is required among women 21 years of age or older. Whereas, in women of 30 to 65 years of age, HR-HPV can be ordered by the clinicians as part of co-testing with any diagnosis and every 5 years with a negative Cervico-Vaginal Pap test (CVPT).

METHODS

A retrospective review of the CoPath database of the Pathology Department at the University of Florida, College of Medicine Jacksonville, FL, was performed to identify North Florida (NF) women who underwent CVPT and HR-HPV testing between 2006 and 2014. The women were stratified by race and age, respectively.

RESULTS

The study included 19,933 CVPTs. Significant differences in the outcomes' distributions were found among age and race groups, respectively. Highest prevalence of HPV positivity was found in African American women, and in 14- to 20-year-old women, respectively. Twenty- to 30-year-old women had the highest percentage (59%) of epithelial abnormality. The most common HR-HPV genotypic distribution was other HR-HPV.

CONCLUSIONS

This study underscores the importance of using both HR-HPV and CVPT for screening for cervical cancer, and confirms the need for special focus on managing high-risk populations subgroups, such as African American women, and women of ages 14 to 20 years especially in high-risk populations.

Community-engaged strategies to promote hepatitis B testing and linkage to care in immigrants of Florida

To improve early identification and linkage to treatment and preventive services for hepatitis B virus (HBV) in persons born in countries with intermediate or high (>2%) HBV prevalence, the University of Florida Center for HIV/AIDS Research, Education, and Services (UF CARES) employed community-engaged strategies to implement the Hepatitis B Awareness and Service Linkage (HBASL) program. In this brief report, we present a summary of program components, challenges, and successes. Faith and community-based networks were established to improve HBV testing and screening and to increase foreign born nationals (FBNs) access to HBV care. A total of 1516 FBNs were tested and screened for hepatitis B. The majority were females (50.4%), Asians (62.8%), non-Hispanic (87.2%), and they also received post-test counseling (54.8%). Noted program advantages included the development of community networks and outreach to a large population of FBNs. The major challenges were institutional delays, pressures related to meeting program deliverables, and diversity within FBNs populations. Community health workers in the United States can replicate this program in their respective communities and ensure success by maintaining a strong community presence, establishing partnerships and linkage processes, developing a sustainability plan, and ensuring the presence of dedicated program staff.

Capillary haemangioma in a 13-year-old boy

This case presents a 13-year-old boy who developed an unusual skin lesion on his chest that occurred after 2-3 weeks following a traumatic injury. The lesion was raised and bled easily. It was surgically removed via shave excision and treated with electrocautery. The patient healed with no recurrence and minimal scarring. Pathology determined the skin lesion to be a capillary haemangioma.

Urine drug test interpretation: what do physicians know?

OBJECTIVE

To determine the level of urine drug test (UDT) interpretive knowledge of physicians who use these instruments to monitor adherence in their patients on chronic opioid therapy.

METHODS

A seven-question instrument consisting of six five-option, single-best-answer multiple choice questions and one yes/no question was completed by 114 physicians (77 who employ UDT and 37 who do not) attending one of three regional opioid education conferences. We calculated frequencies and performed chi2 analyses to examine bivariate associations between UDT utilization and interpretive knowledge.

RESULTS

The instrument was completed by 80 percent of eligible respondents. None of the physicians who employ UDT answered all seven questions correctly, and only 30 percent answered more than half correctly. Physicians who employ UDT performed no better on any of the questions than physicians who do not employ UDT.

CONCLUSIONS

Physicians who employ UDT to monitor patients receiving chronic opioid therapy are not proficient in test interpretation. This study highlights the need for improved physician education; it is imperative for physicians to work closely with certified laboratory professionals when ordering and interpreting these tests.

Karyotypes found in the population declared at increased risk of Down syndrome following maternal serum screening

Of the 65 328 pregnancies of South Australian mothers screened by the South Australian Maternal Serum Antenatal Screening (SAMSAS) Programme between 1 January 1991 and 31 December 1997, 3431 (5.25%) were declared at increased risk of fetal Down syndrome. Fetal or neonatal karyotype was determined in 2737/3431 (79.8%) of these pregnancies, including 16 with early fetal loss. Interrogation of the database of the South Australian Neonatal Screening Service showed 643 live-born infants whose phenotype was not subsequently questioned among the 694 pregnancies whose karyotype was not determined. Of the remaining 51/3431 pregnancies, 19 ended in early fetal loss without karyotyping and no newborn screening or other records could be found for 32 cases. The 129 instances of abnormal karyotype found were Down syndrome (84), trisomy 18 (four), trisomy 13 (three), triploidy (two), female sex chromosome aneuploidy (six) and male sex chromosome aneuploidy (five), inherited balanced rearrangements (19), mosaic or de novo balanced abnormalities (four) and unbalanced karyotypes (two). In the pregnancies declared at increased risk of fetal Down syndrome, only the karyotype for Down syndrome occurred with a frequency greater than that expected for the general, pregnant population.

Fungal infection of the diabetic foot: two distinct syndromes

AIMS

Fungal infection of diabetic foot ulcers has not been described. We analysed the features of 17 patients with diabetic foot ulcers probably infected with fungi.

METHODS

Seventeen patients were identified with clinically infected foot ulcers, (i) which had failed to heal despite prolonged antibiotic therapy and intensive podiatric care, (ii) from which Candida spp. was isolated or hyphae +/- yeasts were visualized in material from ulcers or surrounding skin.

RESULTS

Multiple ulcers arising simultaneously were present in 10 patients (59%), preceded by blistering in seven cases. Single ulcers with markedly ulcerated margins were present in seven (41%) patients and were preceded by blisters in two. All 17 cases had neuropathy and 15 (88%) had severe peripheral vascular disease. All ulcers responded to antifungal therapy.

CONCLUSIONS

Candida spp. is associated with two distinctive patterns of protracted ulceration in diabetic feet which improve following systemic antifungal therapy. Diabet. Med. 18, 567-572 (2001)

Foot problems in patients with systemic sclerosis

OBJECTIVES

To assess the nature of the foot problems experienced in patients with systemic sclerosis (SSc) and patient awareness of such problems.

METHODS

Fifty unselected patients (42 females, eight males) with SSc were assessed by means of examination by a senior podiatrist, completion of a questionnaire detailing past and present foot problems, determination of random plasma glucose, plain X-rays of the feet, and measurement of the ankle/brachial index and of digital pulses by Doppler ultrasound.

RESULTS

Eighty-six per cent of patients reported colour changes in their feet in response to temperature changes, 82% reported pain usually related to cold, 26% had suffered foot ulceration and 8% had a history of foot surgery. Podiatry assessment confirmed the presence of significant abnormalities, including ulcerations in 10%, pre-ulcerative lesions in 34%, toenail changes in 62%, callus formation in 80% and calcinosis in 18%. Forty per cent of the patients had problems with the fitting of shoes, and 19% had been provided with footwear from the hospital. Plain films of the feet demonstrated the presence of erosions in 6%, soft-tissue calcification in 17%, osteopenia in 26% and degenerative changes in 60% of cases. Ten per cent of the patients had an abnormal ankle brachial index (less than 1.0). Only 21% of the 47 patients in whom digital pulses were examined had normal pulses in all toes, and in 26% all toe pulses were absent.

CONCLUSION

Although problems with the hands are well recognized in SSc, foot problems also occur in the majority of patients, and can be a cause of major disability. Care of the feet is therefore an important part of the management of SSC.

Developmental and behavioural outcome in obstetric brachial plexus palsy

Forty-four children with obstetric brachial plexus palsy were assessed for both developmental attainment and behavioural problems. Analysis of the resulting data revealed developmental and behavioural problems previously not identified, particularly in those with more severe injuries. These effects were independent of the general condition of the child at birth, as indicated by their Apgar scores. Further studies are required to provide clarification of these children's difficulties, the mechanisms by which they occur and effective strategies to address them.

The yeast SEN1 gene is required for the processing of diverse RNA classes

A single base change in the helicase superfamily 1 domain of the yeast Saccharomyces cerevisiae SEN1 gene results in a heat-sensitive mutation that alters the cellular abundance of many RNA species. We compared the relative amounts of RNAs between cells that are wild-type and mutant after temperature-shift. In the mutant several RNAs were found to either decrease or increase in abundance. The affected RNAs include tRNAs, rRNAs and small nuclear and nucleolar RNAs. Many of the affected RNAs have been positively identified and include end-matured precursor tRNAs and the small nuclear and nucleolar RNAs U5 and snR40 and snR45. Several small nucleolar RNAs co-immunoprecipitate with Sen1 but differentially associate with the wild-type and mutant protein. Its inactivation also impairs precursor rRNA maturation, resulting in increased accumulation of 35S and 6S precursor rRNAs and reduced levels of 20S, 23S and 27S rRNA processing intermediates. Thus, Sen1 is required for the biosynthesis of various functionally distinct classes of nuclear RNAs. We propose that Sen1 is an RNA helicase acting on a wide range of RNA classes. Its effects on the targeted RNAs in turn enable ribonuclease activity.

Toe to hand transfer in children. Part 2: Functional and psychological aspects

Forty children with congenital (85%) or acquired hand disorders underwent transfer of one or two toes to one hand. The children were reviewed with their parents and assessed for functional and psychosocial performance. There was some evidence that the older the child at the time of transfer, the better the range of motion. The passive range of motion was on average 60 degrees more than the active range of motion despite subsequent procedures such as tenolysis. All transfers recovered protective sensibility and the majority recovered good levels of two point discrimination and light touch perception. Almost all transfers were naturally incorporated into the use pattern of the limb for some or most of the time. Most parents and patients reported a very positive effect of this surgery on the child's psychosocial functioning.

SEN1, a positive effector of tRNA-splicing endonuclease in Saccharomyces cerevisiae

The SEN1 gene, which is essential for growth in the yeast Saccharomyces cerevisiae, is required for endonucleolytic cleavage of introns from all 10 families of precursor tRNAs. A mutation in SEN1 conferring temperature-sensitive lethality also causes in vivo accumulation of pre-tRNAs and a deficiency of in vitro endonuclease activity. Biochemical evidence suggests that the gene product may be one of several components of a nuclear-localized splicing complex. We have cloned the SEN1 gene and characterized the SEN1 mRNA, the SEN1 gene product, the temperature-sensitive sen1-1 mutation, and three SEN1 null alleles. The SEN1 gene corresponds to a 6,336-bp open reading frame coding for a 2,112-amino-acid protein (molecular mass, 239 kDa). Using antisera directed against the C-terminal end of SEN1, we detect a protein corresponding to the predicted molecular weight of SEN1. The SEN1 protein contains a leucine zipper motif, consensus elements for nucleoside triphosphate binding, and a potential nuclear localization signal sequence. The carboxy-terminal 1,214 amino acids of the SEN1 protein are essential for growth, whereas the amino-terminal 898 amino acids are dispensable. A sequence of approximately 500 amino acids located in the essential region of SEN1 has significant similarity to the yeast UPF1 gene product, which is involved in mRNA turnover, and the mouse Mov-10 gene product, whose function is unknown. The mutation that creates the temperature-sensitive sen1-1 allele is located within this 500-amino-acid region, and it causes a substitution for an amino acid that is conserved in all three proteins.

Genetic analysis of a transposable suppressor gene in Saccharomyces cerevisiae

We have demonstrated in Saccharomyces cerevisiae the transposition of a gene coding for an efficient ochre (UAA) suppressor from a centromere-linked site on chromosome III to two new sites in the yeast genome. One site is on chromosome VI, very close to, if not allelic with, SUP11, one of eight genes coding for a tyrosine-inserting suppressor. The second site is on chromosome III, unlinked to the centromere and distal to the mating type locus. This site is very close to those mapped for the recessive lethal amber suppressors, SUP-RL1 and SUP61.