Disease relevance of ATARP4

• Phenotypic analysis of the arp4-1 mutant allele, which has a T-DNA insertion in the promoter region and a moderate reduction in the level of AtARP4 protein expression, revealed partial sterility due to defects in anther development [1].

High impact information on ATARP4

• The nuclear actin-related protein ARP6 is a pleiotropic developmental regulator required for the maintenance of FLOWERING LOCUS C expression and repression of flowering in Arabidopsis [2].
• We examined the subcellular localization, expression patterns, and loss-of-function phenotypes for this protein and found that Arabidopsis ARP6 is localized to the nucleus during interphase but dispersed away from the chromosomes during cell division [2].
• Arabidopsis thaliana ARP6 is a clear homolog of other eukaryotic ARP6s, including Saccharomyces cerevisiae ARP6, which was identified as a component of the SWR1 chromatin remodeling complex [2].
• These results indicate that ARP6 acts in the nucleus to regulate plant development, and we propose that it does so through modulation of chromatin structure and the control of gene expression [2].
• Mutations in actin-related proteins 2 and 3 affect cell shape development in Arabidopsis [3].

Biological context of ATARP4

• ESD1 encodes ARP6, a homolog of the actin-related protein family that shares moderate sequence homology with conventional actins [4].
• Based on our results and data on the yeast ortholog of AtARP4, these two nuclear plant ARPs may be involved in the modulation of chromatin structure and transcriptional regulation mainly in interphase cells [5].
• Recent results from several groups indicate that 'distorted group' genes encode subunits of the actin-related protein (Arp)2/3 and WAVE complexes, and function in a cell morphogenesis pathway [6].
• Western blot analysis and immunolabeling demonstrated a clear correlation between reductions in the level of AtARP4 expression and severity of the phenotypes [1].
• Silencing the nuclear actin-related protein AtARP4 in Arabidopsis has multiple effects on plant development, including early flowering and delayed floral senescence [1].

Other interactions of ATARP4

• Using isovariant-specific monoclonal antibodies, AtARP4 and AtARP7 proteins were shown to be most highly expressed in flowers [7].
• This report shows that the use of live markers for actin visualisation may affect motility of cellular compounds and underlines the general need for critical investigation of actin-related processes in wild-type as well as transgenic plants prior to further interpretation [8].

Analytical, diagnostic and therapeutic context of ATARP4

• Immunofluorescence studies showed that both AtARP4 and AtARP7 were localized predominantly to the nucleus during interphase [5].

References