Alan Kessler, Ph.D., RNA Molecular Biology Laboratory, NIAMS

Contact Information

Summary

Alan Kessler, Ph.D., earned his Bachelor of Science in Biology from the Indiana University of Pennsylvania. He then attended Ohio State University, where he joined Juan Alfonzo's laboratory to study tRNA processing and modification. In the Alfonzo lab, Dr. Kessler focused on tRNA tyrosine in *Trypanosoma brucei*, which is notable for being the only tRNA in the species that contains an intron. He investigated how the compartmentalization of processing enzymes regulates the organism, emphasizing the importance of splicing and modifying this particular tRNA.

Research Statement

Dr. Kessler's research primarily focuses on tRNA. During graduate school, he studied various aspects, including tRNA splicing, processing, and nucleotide modification. At the National Institutes of Health (NIH), he investigates how pre-tRNA can activate the innate immune system and potentially serve as a sensor for viral infections. He also explores the relationship between the pre-tRNA form and the tRNA chaperone La protein.

Dr. Kessler specializes in developing innovative RNA sequencing methods to analyze pre-tRNA and other RNAs transcribed by RNA polymerase III (Pol III). This approach allows us to identify the specific sequences of pre-tRNAs and reveals a significant diversity in both the sequence and length of pre-tRNAs originating from a single gene. Additionally, Dr. Kessler is investigating a patient mutation in the La protein and its potential effects on cellular biology, which may contribute to disease pathology.

Scientific Publications

Key RNA-binding domains in the La protein establish tRNA modification levels in Trypanosoma brucei.

Gunaratne L, Moore H, Albaum N, Casius A, Henderson J, Kessler A, Hegedűsová E, Kulkarni S, Arthur H, Ross RL, Paris Z, Maraia R, Lowe TM, Alfonzo JD

Nucleic Acids Res.

2025 Jul 8;

53(13).

doi: 10.1093/nar/gkaf594

PMID: 40637228

A tRNA gene potential to activate interferon signaling involves selective termination and is suppressible by La protein/SSB.

Kessler AC, Mattijssen S, Margolin GH, Prochnau JY, Iben JR, Li T, Gaidamakov S, Schowe IP, Hafner M, Maraia RJ

Nucleic Acids Res.

2025 Jul 8;

53(13).

doi: 10.1093/nar/gkaf513

PMID: 40637226

Dynamic queuosine changes in tRNA couple nutrient levels to codon choice in Trypanosoma brucei.

Dixit S, Kessler AC, Henderson J, Pan X, Zhao R, D'Almeida GS, Kulkarni S, Rubio MAT, Hegedűsová E, Ross RL, Limbach PA, Green BD, Paris Z, Alfonzo JD

Nucleic Acids Res.

2021 Dec 16;

49(22).

doi: 10.1093/nar/gkab1204

PMID: 34883512

The nuclear and cytoplasmic activities of RNA polymerase III, and an evolving transcriptome for surveillance.

Kessler AC, Maraia RJ

Nucleic Acids Res.

2021 Dec 2;

49(21).

doi: 10.1093/nar/gkab1145

PMID: 34850129

The leucine-NH4+ uptake regulator Any1 limits growth as part of a general amino acid control response to loss of La protein by fission yeast.

Cherkasova V, Iben JR, Pridham KJ, Kessler AC, Maraia RJ

PLoS One.

2021;

16(6).

doi: 10.1371/journal.pone.0253494

PMID: 34153074

Retrograde nuclear transport from the cytoplasm is required for tRNA(Tyr) maturation in T. brucei.

Kessler AC, Kulkarni SS, Paulines MJ, Rubio MAT, Limbach PA, Paris Z, Alfonzo JD

RNA Biol.

2018;

15(4-5).

doi: 10.1080/15476286.2017.1377878

PMID: 28901827

Education

The Ohio State University
PhD in Microbiology (2012-2018)

Indiana University of Pennsylvania
BS in Biology (2008-2012)

Experience

Postdoctoral Fellowship
NIH (2019-Current)

Postdoctoral Fellowship
The Ohio State University (2018-2019)

Graduate Research Fellow
The Ohio State University (2012-2018)