1.A.8.10.1
Tonoplast intrinsic protein, TIPA or Tip3.1, of 268 aas and 6 TMSs.  Phylogenetic distribution, structure, transport dynamics, gating mechanism, sub-cellular localization, tissue-specific expression, and co-expression of TIPs have been reviewed to define their versatile role in plants (Sudhakaran et al. 2021). Based on the phylogenetic distribution, TIPs are classified into five distinct groups with aromatic-arginine (Ar/R) selectivity filters, typical pore-morphology, and tissue-specific gene expression patterns. The tissue-specific expression of TIPs is conserved among diverse plant species, especially for TIP3s, which are expressed exclusively in seeds. The solute specificities of TIPs plays a role in physiological processes like stomatal movement and vacuolar sequestration as well as in alleviating environmental stress. TIPs also play a role in growth and developmental processes like radicle protrusion, anther dehiscence, seed germination, cell elongation, and expansion. The gating mechanism of TIPs regulates the solute flow in response to external signals, which helps to maintain the physiological functions of the cell (Sudhakaran et al. 2021).