Genomewide comparative phylogenetic and molecular evolutionary analysis of tubby-like protein family in Arabidopsis, rice, and poplar

Abstract

Tubby-like proteins, which are characterized by a highly conserved tubby domain, play an important role in the maintenance and function of neuronal cells during postdifferentiation and development in mammals. In additional to the tubby domain, most tubby-like proteins in plants also possess an F-box domain. Plants also appear to harbor a large number of TLP genes. To gain insight into how TLP genes evolved in plants, we conducted a comparative phylogenetic and molecular evolutionary analysis of the tubby-like protein gene family in Arabidopsis, rice, and poplar. Genomewide screening identified 11 TLP genes in Arabidopsis, 14 in rice, and 11 in poplar. Phylogenetic trees, domain organizations, and intron/exon structures classified this family into three subfamilies and indicated that species-specific expansion contributed to the evolution of this family in plants. We determined that in rice and poplar, the tubby-like protein family had expanded mainly through segmental duplication events. Tissue-specific expression analysis indicated that functional diversification of the duplicated TLP genes was a major feature of long-term evolution. Our results also demonstrated that the tubby and F-box domains had co-evolved during the evolution of proteins containing both domains.

Differential expression of TLP, ERF1, and R2R3MYB in annual Medicago species under salinity conditions

“…Boggon et al (1999) found that the Tubby protein is a bipartite transcription regulator and that its N-terminal segment is involved in modulating transcription. In plants, Tubby proteins contain a conserved F-box domain (Liu, 2008;Yang et al, 2008). Fbox proteins regulate diverse cellular processes, including cell cycle transition, transcriptional regulation, and signal transduction.…”

New insights into the subcellular localization of Tubby-like proteins and their participation in theArabidopsis-Piriformospora indicainteraction

“…Arabidopsis-Piriformospora indica interaction [16][17][18] In Arabidopsis, AtTLP9 acts in ABA signaling during germination and plays a role in responses to salt and drought stress. 17,19 Consistent with this, a TLP from chickpea was recently demonstrated to confer increased tolerance to salt, drought and oxidative stress when overexpressed in tobacco.…”

“…23 Therefore, we fused GFP N-terminally to the Tubby domain of a barley (Hordeum vulgare) TLP (GenBank: AK251904.1) designated HvTLP12 for its similarity to rice TLP12. 18 The chimera (GFP-HvTLP12Δ1-123), was observed at the PM when expressed in Arabidopsis leaf epidermal cells (Fig. 3D).…”

Interactions between wheat Tubby-like and SKP1-like proteins

“…Tubby and Tubby-like proteins, which were initially linked to the spontaneous maturity-onset obesity syndrome in mice, were later shown to be involved in the development and functions of neuronal cells during post-differentiation in mice (Coleman and Eicher, 1990;Kleyn et al, 1996;Li et al, 2001;Ikeda et al, 2002;Yang et al, 2008). TULPs play crucial roles in photoreceptor degradation (Ikeda et al, 1999), embryonic lethality (Nishina et al, 1998) and membrane receptor trafficking (Mukhopadhyay et al, 2010).…”

“…Tubby proteins are highly conserved among different species of mammals, while TULPs are found in a wide range of multicellular organisms (Boggon et al, 1999;Lai et al, 2004). Tubby and TULPs are characterized by a conserved Tubby domain (approximately 270 amino acids) located at the C terminus (North et al, 1997;Yang et al, 2008;. The N-terminal region of Tubby proteins in humans is less conserved than the Cterminal region, suggesting that the C-terminal region is functionally redundant among the Tubby gene family members (Ikeda et al, 1999;Ikeda et al, 2001).…”