Identifying Mu Insertions in Nutrient Transport-related Genes in the UniformMu Maize Population

Overview:Research presented here tests the hypotheses that insertion of a Mu transposable element into any of the selected genes will cause a loss of function that results in a distinct mutant phenotype. The UniformMu maize population is a resource developed by introgressing the highly transposon-mutagenic line Robertson’s Mutator into the phenotypically-uniform inbred W22. This population provides the ability to identify and map Mu insertions, allowing researchers to select and characterize lines harboring mutations in genes of interest. Here we use both a forward and reverse genetics approach to identify insertions in genes potentially affecting nutrient transport. To this end, we attempt to associate insertions with mutant phenotypes through co-segregational analyses.

Stephanie M. Locke, Brent. A. O’Brien, Ryan Gannon, Johnathan Saunders, Laura Morales,

Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL, 32611

References: McCarty, D.R., Settles, A.M., Suzuki, M., Tan, B.C., and Latshaw, S. et al. (2005). Steady-state transposon mutagenesis in inbred maize. Plant J. 44: 52-61.

Localizes to the plasmodesmata and is predicted to bind callose, which is deposited at the sieve plate in response to injury and pathogen infection.GRMZM2G125241

Plasmodesmata callose binding protein 4 (PDCB4)

ABC (ATP binding cassette) transporters are transmembrane proteins that utilize the energy of ATP hydrolysis to pump substrate across the membrane against a concentration gradient.GRMZM2G156630

ABC-type transporter

Primarily functions in carbohydrate bindingIn A. Thaliana, this gene was found to be a N-terminal protein involved in myristoylation and control responses to phloem damage.GRMZM2G010855

Phloem protein 2A13 (PP2 A13)

This gene functions in carbohydrate transmembrane transporter activity.GRMZM2G160504GRMZM2G160460

Solute carrier family 2, facilitatedglucose transporter member 8 (SLC2A8)

Hydrolyzes sucrose to fructose and glucose in the cytoplasmGRMZM2G084940

Plant neutral invertase family protein

SCF23 represents integral membrane proteins that transport organic molecules and inorganic ions.GRMZM2G437859

Solute carrier family 23 member 2 (SCF23)

Reverse Genetics

Forward GeneticsFamily 011S-2189Phenotype = wilty

Insertions Tested

Segregation/genotypesInsertions Testedwith main phenotypes

Co-segregation

Mitochondrial transcription termination factor family protein

Long-chain acyl-CoA synthetase 7

Hercules receptor kinase 2

Protein of unknown function (DUF3537)

Peptidase M1 family protein

PapD-like superfamily protein

Sec-independent periplasmic protein translocase

Cellulose synthase-like D3

Succinate dehydrogenase 1-1

Segregation/genotypes KO with phenotypeCo-segregation of

Prominent Phenotypes

WT, Het, and Homozygous

WT, Het, and Homozygous

WT, Het, and Homozygous

WT, Het, and Homozygous

WT, Het, and HomozygousWT, Het, and Homozygous

WT, Het, and Homozygous

All WT

WT, and Homozygous

NO

NO

NO

NO

NO

NONO

NO

--

Empty pericarp (ep)Embryo lethal (emb)Leaf discoloration

Defective kernel (dek), Rough kernel (rgh), ep,

and emb

Small kernel (smk),ep, and emb

smk and emb

ep and dek

smk

WT, Het, and Homozygous

PCR inconclusive to date

All Het or WT (GRMZM2G160504)

All Het (GRMZM2G160460)

WT, Het, and Homozygous

All Het

WT, Het, and Homozygous

?

NO(other effects possible)

ep

smk Leaf discoloration

emb

Phenotype Examples

NO(other effects possible)

NO(other effects possible)

NO(other effects possible)

NO(other effects possible)

Wayne T. Avigne, Donald McCarty, Charles Hunter, and Karen E. Koch

Wild type