Integrated femtosecond stimulated Raman scattering and two-photon fluorescence imaging of subcellular lipid and vesicular structures

Li, Xuesong; Lam, Wen Jiun; Cao, Zhe; Hao, Yan; Sun, Qiqi; He, Sicong; Mak, Ho Yi; Qu, Jianan Y.

doi:10.1117/1.jbo.20.11.110501

Cited by 12 publications

(15 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We focused our phenotypic analysis on the intestine, which is the major site of fat storage in C. elegans 2 . Using label-free stimulated Raman scattering (SRS) 40 , we did not detect significant difference in neutral fat storage between seip-1 mutants and wild-type animals (Fig. 1b).…”

Section: Resultsmentioning

confidence: 92%

“…For analyzing single lipid droplets, an integrated femtosecond (fs) stimulated Raman scattering (SRS) and two-photon excited fluorescence (TPEF) microscope system was used for label-free imaging of LDs in C. elegans 40 . L4 larval animals ( hjSi3 ) were dissected in the physiological buffer (150 mM NaCl, 3 mM KCl, 2 mM MgCl 2 , 3 mM CaCl 2 , 10 mM glucose and 15 mM HEPES; 340–345 mmol/kg) containing 0.2 mM levamisole and mounted on a 2% agarose pad.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

et al. 2019

Self Cite

View full text Add to dashboard Cite

Exogenous metabolites from microbial and dietary origins have profound effects on host metabolism. Here, we report that a sub-population of lipid droplets (LDs), which are conserved organelles for fat storage, is defined by metabolite-modulated targeting of the C. elegans seipin ortholog, SEIP-1. Loss of SEIP-1 function reduces the size of a subset of LDs while over-expression of SEIP-1 has the opposite effect. Ultrastructural analysis reveals SEIP-1 enrichment in an endoplasmic reticulum (ER) subdomain, which co-purifies with LDs. Analyses of C. elegans and bacterial genetic mutants indicate a requirement of polyunsaturated fatty acids (PUFAs) and microbial cyclopropane fatty acids (CFAs) for SEIP-1 enrichment, as confirmed by dietary supplementation experiments. In mammalian cells, heterologously expressed SEIP-1 engages nascent lipid droplets and promotes their subsequent expansion in a conserved manner. Our results suggest that microbial and polyunsaturated fatty acids serve unexpected roles in regulating cellular fat storage by promoting LD diversity.

show abstract

Section: Resultsmentioning

confidence: 92%

Section: Methodsmentioning

confidence: 99%

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Using label-free Stimulated Raman Scattering (SRS) 39 , we did not detect significant difference in neutral fat storage between seip-1 mutant and wild type animals ( Figure 1B).…”

Section: Seip-1 Regulates Ld Sizementioning

confidence: 95%

“…Label-free Lipid Imaging in C. elegansFor analyzing single lipid droplets, an integrated femtosecond (fs) stimulated Raman scattering (SRS) and two-photon excited fluorescence (TPEF) microscope system was used for label-free imaging of LDs in C. elegans39 . L4 larval animals (hjSi3) were dissected in the physiological buffer (150mM NaCl, 3mM KCl, 2mM MgCl2, 3mM CaCl2, 10mM glucose and 15mM HEPES; 340-345mmol/kg) containing 0.2mM levamisole and mounted on a 2% agarose pad.…”

mentioning

confidence: 99%

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

Cao

Hao

Lee

et al. 2018

Preprint

Self Cite

View full text Add to dashboard Cite

Exogenous metabolites from microbial and dietary origins have profound effects on host metabolism. Here, we report that a sub-population of lipid droplets (LDs), which are conserved organelles for fat storage, is defined by metabolites-driven targeting of the C. elegans seipin ortholog, SEIP-1. Loss of SEIP-1 function reduced the size of a subset of LDs while over-expression of SEIP-1 had the opposite effect. Ultrastructural analysis revealed SEIP-1 enrichment in an endoplasmic reticulum (ER) subdomain, which co-purified with LDs. Analyses of C. elegans and bacterial genetic mutants indicated a requirement of polyunsaturated fatty acids (PUFAs) and microbial cyclopropane fatty acids (CFAs) for SEIP-1 enrichment, as confirmed by dietary supplementation experiments. In mammalian cells, heterologous expression of SEIP-1 promoted lipid droplet expansion from ER subdomains in a conserved manner. Our results suggest that microbial and polyunsaturated fatty acids serve unexpected roles in regulating cellular fat storage by enforcing LD diversity.

show abstract

“…To visualize LDs of wild type and mutant animals, we used a recently developed Stimulated Raman Scattering (SRS) microscopy system (Li et al, 2015). We focused on detecting C-H bond vibration from TAG, which was highly concentrated in LDs.…”

Section: Tmem-120 Is Required For Tag Accumulation and Ld Expansionmentioning

confidence: 99%

The endoplasmic reticulum-resident protein TMEM-120/TMEM120A promotes fat storage in C. elegans and mammalian cells

Huang

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

The synthesis of triacylglycerol (TAG) is essential for the storage of excess fatty acids, which can subsequently be used for energy or cell growth. A series of enzymes act in the endoplasmic reticulum (ER) to synthesize TAG, prior to its transfer to lipid droplets (LDs), which are conserved organelles for fat storage. Here, we report that the deficiency of TMEM-120/TMEM120A, a protein with 6-transmembrane helices, retards TAG synthesis and LD expansion in C. elegans. GFP fusion proteins of TMEM-120, expressed at the endogenous level in live worms, were observed throughout the ER network. Using Stimulated Raman Scattering, we demonstrated the specific requirement of TMEM-120 in the storage of exogenous fatty acids in LDs. Knockdown of TMEM120A impedes adipogenesis of pre-adipocytes in vitro, while its over-expression is sufficient to promote LD expansion in mammalian cells. Our results suggest that TMEM-120/TMEM120A plays a conserved role in increasing the efficiency of TAG synthesis.

show abstract

Integrated femtosecond stimulated Raman scattering and two-photon fluorescence imaging of subcellular lipid and vesicular structures

Cited by 12 publications

References 21 publications

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

Dietary fatty acids promote lipid droplet diversity through seipin enrichment in an ER subdomain

The endoplasmic reticulum-resident protein TMEM-120/TMEM120A promotes fat storage in C. elegans and mammalian cells

Contact Info

Product

Resources

About