Changes in inflorescence protein during advanced stages of floret development in Buchloe dactyloides (Poaceae)

Abstract

ABSTRACT. Buffalograss, Buchloe dactyloides, is a dioecious species native to the Great Plains of North America. The florets at the early stages of development possess both gynoecium and androecium organ primordia but later become unisexual. Very little is known about the proteomic changes that occur when the florets change from hermaphroditism to unisexuality. We compared the protein composition of florets at the hermaphroditic stage with that at the unisexual stage. The development stage of the floret was determined by stereomicroscopic observation. Two-dimensional gel electrophoresis was used to separate the proteins extracted from female and male inflorescences. Stagespecific protein maps, with an average of about 400 spots per map, were analyzed with the protein analysis software. Eighteen spots were found to be differentially expressed between the hermaphrodite and unisexual stages. Of these, 12 were present at both stages but with a different expression value. Four specific spots appeared at the hermaphrodite stage and disappeared at the unisexual stage. Two specific protein spots were associated with female and male floret differentiation. One appears to be associated with contabescence in the female floret and the final protein appears to lead to the abortion of gynoecium in the male floret. The MALDI TOF/TOF technique was used for peptide mass fingerprinting of the differentially expressed proteins and the MASCOT software was used to search the protein database. However, only two protein spots were identified from the database. These were aldolase1 and Os05g0574400 (similar to malate dehydrogenase). This type of proteomic study can help to identify novel protein products and determine the mechanisms involved in the floral sex differentiation process in buffalo grass.

Proteomics: a promising tool for research on sex-related differences in dioecious plants

“…A complex sex determination mechanism has been found in Mercurialis annua , in which the sex is controlled by multiple unlinked loci (Janousek and Mrackova, 2010 ). Recently, much research on dioecious plants has focused on sex-linked genes (e.g., Blavet et al, 2015 ; Harkess et al, 2015 ; Jia et al, 2015 ) and sex-related differences (e.g., Chen et al, 2011 , 2013 ; Zhou et al, 2012 ; Liu et al, 2013 ; Xiong et al, 2013 ; Juvany et al, 2014 ; Deng et al, 2015 ; Juvany and Munné-Bosch, 2015 ).…”

Molecular Differentiation of Gender in Buffalograss

“…The Tasselseed1 and Tas-selseed2 genes had previously been shown to be important for flowering in maize (Acosta et al, 2009;DeLong et al, 1993). Using 2-D polyacrylamide gel electrophoresis, buffalograss protein expression changes were evaluated during two stages of inflorescence development and 18 sex-linked proteins were identified along with two that were annotated (Zhou et al, 2012). One was identified as an aldolase1 (gi|162462282) and the other is similar to malate dehydrogenase (gi|115465579).…”