D‐3‐phosphoglycerate dehydrogenase from the silkworm Bombyx mori: Identification, functional characterization, and expression. Issue 1 (14th October 2020)

• Record Type: Journal Article
• Authors: Yamamoto, Kohji; Mohri, Shinya; Furuya, Shigeki
• Is Part Of: Archives of insect biochemistry and physiology. Volume 106:Issue 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-10-14
• Subjects: Bombyx mori -- D‐3‐phosphoglycerate dehydrogenase -- NADH -- serine; Insects -- Physiology -- Periodicals; Insect biochemistry -- Periodicals; 595.701572
• DOI: 10.1002/arch.21751
• Languages: English
• ISSNs: 0739-4462

Abstract

Abstract: D‐3‐phosphoglycerate dehydrogenase (PHGDH) is a key enzyme involved in the synthesis of l ‐serine. Despite the high serine content in silk proteins and the crucial role of PHGDH in serine biosynthesis, PHGDH has not been described in silkworms to date. Here, we identified PHGDH in the silkworm Bombyx mori and evaluated its biochemical properties. On the basis of the amino acid sequence and phylogenetic tree, this PHGDH has been categorized as a new type and designated as bmPHGDH. The recombinant bmPHGDH was overexpressed and purified to homogeneity. Kinetic studies revealed that PHGDH uses NADH as a coenzyme to reduce phosphohydroxypyruvate. High expression levels of bmphgdh messenger RNA (mRNA) were observed in the middle part of the silk gland and midgut in a standard strain of silkworm. Moreover, a sericin‐deficient silkworm strain displayed reduced expression of bmphgdh mRNA. These findings indicate that bmPHGDH might play a crucial role in the provision of l ‐serine in the larva of B. mori . Abstract : Analysis of the expression of bmPHGDH‐encoding transcripts. Real‐time quantitative polymerase chain reaction was carried out to detect bmphgdh messenger RNA (mRNA) in various organs of the p50T strain (a), in the middle silk glands (b), and in the midgut of p50T and b94 strains (c). Black and gray bars indicate results for p50T and b94, respectively. Data were normalized to rp49 mRNA levels. Highlights: We identified a D‐3‐phosphoglycerate dehydrogenase (PHGDH), bmPHGDH, in silkworm, which reduces phosphohydroxypyruvate. Our findings suggest that bmPHGDH might play a crucial role in the provision of l ‐serine in the larva of a silkworm.