A protein shown in any one of (a) to (e) below: (a) a protein consisting of the amino acid sequence shown in SEQ ID NO: 2; (b) a protein which consists of an amino acid sequence with deletion, substitution or addition of 1 to 50 amino acids in SEQ ID NO: 2 and which has phosphatidic acid phosphatase activity; (c) a protein which consists of an amino acid sequence sharing an identity of 85% or more with the amino acid sequence consisting of SEQ ID NO: 2 and which has phosphatidic acid phosphatase activity; (d) a protein which consists of an amino acid sequence with deletion, substitution or addition of 1 to 50 amino acids in SEQ ID NO: 2 and which has the ability to yield a fatty acid rate ensuring a higher ratio of at least one or more of (i) to (vi) shown below in the fatty acid rate of a host expressing a protein consisting of the amino acid sequence than in the fatty acid rate of a host not expressing the protein: (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content; or (e) a protein which consists of an amino acid sequence sharing an identity of 85% or more with the amino acid sequence consisting of SEQ ID NO: 2 and which has the ability to yield a fatty acid rate ensuring a higher ratio of at least one or more of (i) to (vi) shown below in the fatty acid rate of a host expressing a protein consisting of the amino acid sequence than in the fatty acid rate of a host not expressing the protein: (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content. (a) a protein consisting of the amino acid sequence shown in SEQ ID NO: 2; (b) a protein which consists of an amino acid sequence with deletion, substitution or addition of 1 to 50 amino acids in SEQ ID NO: 2 and which has phosphatidic acid phosphatase activity; (c) a protein which consists of an amino acid sequence sharing an identity of 85% or more with the amino acid sequence consisting of SEQ ID NO: 2 and which has phosphatidic acid phosphatase activity; (d) a protein which consists of an amino acid sequence with deletion, substitution or addition of 1 to 50 amino acids in SEQ ID NO: 2 and which has the ability to yield a fatty acid rate ensuring a higher ratio of at least one or more of (i) to (vi) shown below in the fatty acid rate of a host expressing a protein consisting of the amino acid sequence than in the fatty acid rate of a host not expressing the protein: (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content; or (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content; or (e) a protein which consists of an amino acid sequence sharing an identity of 85% or more with the amino acid sequence consisting of SEQ ID NO: 2 and which has the ability to yield a fatty acid rate ensuring a higher ratio of at least one or more of (i) to (vi) shown below in the fatty acid rate of a host expressing a protein consisting of the amino acid sequence than in the fatty acid rate of a host not expressing the protein: (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content. (i) the oleic acid content; (ii) the ratio of the palmitoleic acid content to the palmitic acid content; (iii) the ratio of the oleic acid content to the palmitic acid content; (iv) the ratio of the total content of stearic acid and oleic acid to the palmitic acid content; (v) the ratio of the C 18 fatty acid content to the C 16 fatty acid content; and (vi) the ratio of the arachidonic acid, dihomo-γ-linolenic acid and/or γ-linolenic acid content.