Disruptions in valine degradation affect seed development and germination in Arabidopsis.
We have functionally characterized the role of two putative mitochondrial enzymes in valine degradation using insertional mutants. Prior to this study, the relationship between branched-chain amino acid degradation (named for leucine, valine and isoleucine) and seed development was limited to leucine catabolism. Using a reverse genetics approach, we show that disruptions in the mitochondrial valine degradation pathway affect seed development and germination in Arabidopsis thaliana. A null mutant of 3-hydroxyisobutyryl-CoA hydrolase (CHY4, At4g31810) resulted in an embryo lethal phenotype, while a null mutant of methylmalonate semialdehyde dehydrogenase (MMSD, At2g14170) resulted in seeds with wrinkled coats, decreased storage reserves, elevated valine and leucine, and reduced germination rates. These data highlight the unique contributions CHY4 and MMSD make to the overall growth and viability of plants. It also increases our knowledge of the role branched-chain amino acid catabolism plays in seed development and amino acid homeostasis.
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Andrew B
AB
Gipson
Doan University, 1014 Boswell Ave, Crete, NE, 68333, USA.
Kyla J
KJ
Morton
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Rachel J
RJ
Rhee
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Szabolcs
S
Simo
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Jack A
JA
Clayton
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Morgan E
ME
Perrett
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Christiana G
CG
Binkley
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Erika L
EL
Jensen
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Dana L
DL
Oakes
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.
Matthew F
MF
Rouhier
Kenyon College, 200 N. College Rd, Gambier, OH, 43022, USA.|Doan University, 1014 Boswell Ave, Crete, NE, 68333, USA.
Kerry A
KA
Rouhier
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D018525:Germination / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D012639:Seeds / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D014633:Valine / Q000378:metabolism*
D029681:Arabidopsis Proteins; D014633:Valine
Arabidopsis; development; embryo lethal; seed; valine catabolism