Maize Genetics Cooperation Newsletter

maize gene review

Author: Alice Barkan, University of Oregon, Eugene, OR USA 97403


Review: pending

Pub date: May 2009

Name: csy1 chloroplast SecY-1

Synonyms: scy1

Chromosome 5S bin 5.03
Genome Browser BAC c0287J03/AC206283, determined by NCBI BLAST. Note that this BAC is on chromosome 10 of the Reference Genome Sequence ver 1.

Function: thylakoid protein translocation

image of corn mutant

Summary: encodes a chloroplast-localized homolog of SecY, the core component of the Sec membrane translocon in prokaryotic organisms. Null csy1 alleles are pale yellow and seedling lethal due to the absence of most thylakoid membrane proteins.

Images: mutant leaf color mutants, on a seedling color scale

First report: Roy and Barkan 1998.

Key Alleles

3 independent alleles identified in a TUSC screen at Pioneer Hi-Bred (Johnston, IA), with same phenotype:

  csy1-1::MuDR, MuDR inserted in first exon.

  csy1-2::Mu1, Mu1 inserted in first exon.

  csy1-3::Mu8, Mu8 inserted in second exon.

Map Location

Maps to chromome 5S, between bnlg1879 and bnl7.56. (see map BNL 2002 5 in MaizeGDB). This location is in conflict with version 1 of the B73 reference genome sequence.

Gene Product

CpSecY: thylakoid Sec-pathway translocase. In prokaryotes, SecY is the core component of the Sec membrane translocon.


Roy LM, Barkan A. (1998) A SecY Homologue Is Required for the Elaboration of the Chloroplast Thylakoid Membrane and for Normal Chloroplast Gene Expression. J Cell Biol 141: 385-395. PUBMED

Links: MGDB: csy1 NCBI Gene: csy1 UniProt: O63066