Direction of DBA Research and Overview

Steven R. Ellis, Ph.D.Professor, Department of Biochemistry

University of Louisville

July 16th 2015Camp Sunshine

Research Director Diamond Blackfan Anemia Foundation

General Trends in DBA Research

Focus on translational research: Bench to bedside

Continued reliance on private Foundations to support DBA research

• Improved drugs• Genetics; gene discovery, genotype/phenotype relationships

• Beyond anemia; syndromic DBA

• 2012 - 3 year, DOD Award to Dr. Lodish -New drugs for anemia treatment based on a new understanding of the mechanisms of stress erythropoiesis

• April 2014 - bridge grant (DBAF) – between years 1 and 2, $21, 281

• August 2014 – program discontinued

• September 2013 – anticipating funds for year 2

• $95,000 awarded to Dr. Lodish (DBAF and DBAC) to continue his work

Your Foundations at Work

4/2015 – DBAF and DBAC awarded a grant of $35,000 to Johan Flygare to help start up a new lab and screen a library of over 12,000 chemical compounds to identify potential drugs that alleviate the symptoms of their mouse model of DBA

• 2008/2009 Johan was a post-doctoral fellow in Harvey Lodish’s laboratory and did the initial work on how glucocorticoids stimulate red cell production

• Prior to 2008, Johan was a graduate student in the laboratory of Stefan Karlsson helping develop the mouse model for DBA which is being used to test gene therapy approaches for DBA

4/2014 – DBAF awarded a grant of $36,000 to Vijay Sankaran to study the role of GATA1 in red cell production with an eye toward novel therapies for DBA

1/2015 – DBAF and DBA UK awarded a grant of $41,810 to Nickolas Watkins to study the role of RPL5 and RPL11 in signaling p53 activation

Physicians li

ke Drs. Vlachos a

nd Lipton will

have their h

ands full w

ith cli

nical tr

ialsIncreased number of potential drugs

coming down the R&D pipeline

Drugs specifically directed at DBA /drugs targeted at the intrinsic nature of genetic diseases

Personalized medicine, drugs as diverse as the heterogeneity of DBA patients

Direction of DBA Research (2015 Predictions)

• A drug may target a subset of DBA genes

• A drug may target a particular type of genetic lesion

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

Met – Phe – Arg – Leu – Ala – Lys – Leu – Lys – Gly – Ser - Term

Central Dogma of Molecular Biology

mRNA

Protein

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

aagcuuccaau//gguccaucguac

transcription

splicing

pre-mRNA

translation

3.5 billion bases

intronexon

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

Met – Phe – Arg – Leu – Ala – Lys – Leu – Lys – Gly – Ser - Term

mRNA

Protein

translationC

Phe

silent/synonymous

U

Term

nonsense/nonsynonymous

frameshift

Mutation Muddle

G

Glu

missense/nonsynonymous

Lys NH3+ Glu COO -

Asp COO -

*

With the Advent of Whole Exome and Whole Genome Sequencing We are Faced with an Increasing Number of

Variants of Unknown Significance (VUS)

An extended family seen by the bone marrow failure unit at the National Cancer Institute• 3 affected family members with a VUS in RPS19• V138L, valine to leucine substitution at position 138

COO -

C HH3+ N

CH

CH3 CH3

COO -

C HH3+ N

CH

CH3 CH3

CH2

V, Valine L, Leucine

LVVIL

human

Gregory (2007) NAR

• The in silico prediction programs are not unanimous about whether this would be a potentially disease causing variant. It does not exist in any public databases.

V138L

The Plot Thickens

Pre-rRNA Processing as a Means of Studying Ribosomal Protein Function

Patients Display a Pre-rRNA Processing Signature Consistent with V138L Being a Pathogenic Mutation

Flygare, Aspesi et al. 2007 Blood

RPS19 Knockdown

✔

✔

PP C

✔

FINAL THOUGHTS

These Folks Represent Only a Fraction of the People Out There Working to Help Your Kids

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

Met – Phe – Arg – Leu – Ala – Lys – Leu – Lys – Gly – Ser - Term

mRNA

Protein

translationC

Phe

silent/synonymous

U

Term

nonsense/nonsynonymous

frameshift

Mutation Muddle

G

Glu

missense/nonsynonymous

Atalurin – a drug that causes ribosomes to read through premature termination codons

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

Met – Phe – Arg – Leu – Ala – Lys – Leu – Lys – Gly – Ser - Term

Mutation Muddle

mRNA

Protein

AUG – UUU – AGG – CUG – GCA – AAG – CUA – AAA – GGA – UCC - UAA

aagcuuccaau//gguccaucguac

transcription

splicing

pre-mRNA

translation

Drugs are in development to fix splicing defects

Physicians li

ke Drs. Lip

ton and Vlachos will

have their h

ands full w

ith cli

nical tr

ialsIncreased number of potential drugs

coming down the R&D pipeline

Drugs specifically directed at DBA /drugs targeted at the intrinsic nature of genetic diseases

Personalized medicine, drugs as diverse as the heterogeneity of DBA patients

Specific Trends in DBA Research

• A drug may target a subset of DBA genes

• A drug may target a particular type of genetic lesion