The present invention relates to isolated nucleic acid molecules and their corresponding encoded polypeptides able confer the trait of improved plant size, vegetative growth, growth rate, seedling vigor and/or biomass in plants challenged with saline conditions. The present invention further relates to the use of these nucleic acid molecules and polypeptides in making transgenic plants, plant cells, plant materials or seeds of a plant having plant size, vegetative growth, growth rate, seedling vigor and/or biomass that are improved in saline conditions with respect to wild-type plants grown under similar conditions.