Anther developmental defects in Arabidopsis thaliana male-sterile mutants

Abstract

We identified Arabidopsis thaliana sterility mutants by screening T-DNA and EMS-mutagenized lines and characterized several male-sterile mutants with defects specific for different anther processes. Approximately 44 and 855 sterile mutants were uncovered from the T-DNA and EMS screens, respectively. Several mutants were studied in detail with defects that included the establishment of anther morphology, microspore production, pollen differentiation, and anther dehiscence. Both non-dehiscencing and late-dehiscencing mutants were identified. In addition, pollenless mutants were observed with either apparent meiotic defects and/or abnormalities in cell layers surrounding the locules. Two mutant alleles were identified for the POLLENLESS3 locus which have defects in functional microspore production that lead to the degeneration of cells within the anther locules. pol-lenless3-1 contains a T-DNA insertion that co-segregates with the mutant phenotype and pollenless3-2 has a large deletion in the POLLENLESS3 gene. The POLLEN-

Genome-Wide Association Mapping of Fertility Reduction upon Heat Stress Reveals Developmental Stage-Specific QTLs in Arabidopsis thaliana

“…This tag enabled us to relate the effect of heat stress to the developmental stage of the flowers and siliques along the inflorescence (Figure 2). In reference to the tag, all siliques received a relative position number and we subsequently defined five developmental regions, A to E. To link the observed reduction in silique length with the disruption of flower development and embryogenesis, we matched the regions as defined in Figure 2 with data regarding timing and order of events taking place during these developmental processes in Arabidopsis (Table 1; Smyth et al, 1990;Mansfield and Briarty, 1991;Schneitz et al, 1995;Sanders et al, 1999). Region A (silique position numbers 220 to 210) is linked to late embryogenesis.…”

“…This resulted in the identification of a candidate gene, QUASIMODO-LIKE2 (QUL2; Smyth et al (1990). b Data are taken from Mansfield and Briarty (1991), Schneitz et al (1995), and Sanders et al (1999). AT2G03480) that is highly expressed during the development of the male gametophyte (Honys and Twell, 2004).…”

Functional conservation and maintenance of expression pattern of FIDDLEHEAD-like genes in Arabidopsis and Antirrhinum

“…Due to the nearly complete sterility of fdh mutants caused by extreme floral-organ fusions, it is very difficult to determine whether the fdh mutant displays delayed anther dehiscence. Several dehiscence mutants are available in Arabidopsis (Sanders et al, 1999) that could be helpful in establishing the role of the FDH gene in the process of cell separation within the stomium. Like FDH, the anther dehiscence genes that have so far been identified molecularly, DEFECTIVE IN ANTHER DEHISCENCE 1 (DAD1) (Ishiguro et al, 2001), DELAYED DEHISCENCE 1 (Sanders et al, 2000) and OPR3 (Stintzi and Browse, 2000), all encode enzymes of lipid metabolism.…”

Global analysis of gene expression in flower buds of Ms-cd1 Brassica oleracea conferring male sterility by using an Arabidopsis microarray

“…A number of stage-specific genes have been isolated and functionally characterized with respect to their role in reproductive biology in Arabidopsis and several other plant species (reviewed in Taylor et al 1997;Sanders et al 1999;reviewed in Ma 2005). However, the genome-wide information of these specific gene expression patterns in relation to their developmental stages is still very limited.…”