LHSI Intern: Chromosomal versus gonadal sex regulation of bone mass

Program Summary:  

This internship is offered as a part of the Life-Health Sciences Internship Program (LHSI). This program connects 125 IUI undergraduates per year with internships on campus with faculty and staff in a variety of health and science related campus areas/programs. All LHSI internships start in August 2025 and end in May 2026 and are paid $13/hour for up to 10 hours per week. Work-study is accepted but not required. 

Supervisor: Dr. Lilian I. Plotkin

Department/Office: Medicine; Anatomy, Cell Biology & Physiology

Overview of the internship site: Chromosomal versus gonadal sex regulation of bone mass. The musculoskeletal system utilizes muscles, bones, and connective tissues to perform simple to complex actions. The structure and mechanical properties of this system differ between sexes (male vs female). The physical characteristics can be attributed to phenotypic differences between sexes (sexual dimorphism), which is has been thought to be the result of the sex hormones present in mice and humans (estrogens secreted by cells in the ovaries and androgens secreted by cells in the testes). However, sexual dimorphism is present prior to the onset of sex hormones, due to the contribution of sex chromosomes. The Four Core Genotype Model (FCG), in which gonadal sex can be independent from sex chromosomes, was developed to isolate the determinants of sexual dimorphism, and we are using this model to determine how these factors influence bone formation and growth. DXA PIXImus imaging and weight measurements are needed for body composition analysis (bone/lean/fat masses). The geometrical structure and mineral content is determined by microcomputized tomography, and the differences in gene expression by quantitative PCR. In summary, the purpose of our studies is to understand the contributions of sex chromosomes (XX vs. XY) and sex steroids (estrogens vs. androgens) to the bone composition and bone mass in young, adult and aged mice, and to investigate the molecular basis for these differences in the bone tissue.

Website for more information: https://medicine.iu.edu/faculty/19291/plotkin-lilian

Essential Duties and Responsibilities:

• Genotyping to identify genetically modified mice
• Analyzing bone mineral density scans
• Microcomputed tomography scanning and analysis
• RNA isolation and gene expression analysis
• Histological analyses of bone tissue sections

Work Environment and Dress Code: The work is performed primarily in a lab setting with dress code 1. Always tie back hair that is chin-length or longer. 2. Make sure that loose clothing or dangling jewelry is secured or avoid wearing it in the first place. 3. Never wear sandals or other open-toed shoes in the lab. Footwear should always cover the foot

Hours per week: 10, scheduling is flexible within regular work hours

Project-specific qualifications: Dependability, adaptability, flexibility to change the course of the experiments based on previous results, ability to work well in a group, in particular with the diverse members of the lab

By the end of the LHSI program, you will:

·        Carefully consider, explore, and articulate your career goals, including an analysis of how you arrived at that path and what steps you need to take next. (Community Contributor, Communicator)

·        Understand your role and strengths on a professional team and analyze who you would like to become as a professional. (Communicator)

·        Gain and strengthen skills relevant to next steps after graduation, such as communication, collaboration, teamwork, analysis/synthesis/evaluation, independence, confronting/challenging failure, problem-solving and perseverance, and constructive criticism. (Problem Solver, Communicator)

·        Convey ideas and knowledge effectively through an ePortfolio and presentation of your internship work. (Problem Solver, Communicator)

·        Set and meet your own additional learning goals identified with your supervisor.

LHSI Qualifications  

·        must be graduating May 2027 or after (usually a current freshman or sophomore in Spring 2025)   

·        Current full-time IUI undergraduate

·        minimum overall GPA of 2.0 

·        All majors welcome

To apply:

LHSI accepts at least 125 interns per year. Complete the application for LHSI at lhsi.indianapolis.iu.edu and select 3-4 internship sites on that application. All available sites are listed in Handshake and will start with the position title “LHSI Intern.” You will meet with at least 2 of these if selected for interviews.